Right now the best bargain in a WWII Rifle to get is also light on recoil BUT the ammo isn't cheap as its all match grade, if ya can grab a nice Walnut stocked K31 they are one of the best and will be very hard to find at the current prices very shortly as the last of them has just been imported.
Next get a NO4MK1 Enfield, right now they are running around $100 be picky and look for the milled vernier rear sight, also look for a clean shiny bore and all matching numbers, All of them will have what looks liked black paint on the metal this was the last refinish they recieved and the stuff is super tough. The Longbranch (Canadian) tends to be the most accurate, The US-Property marked Savage built are the rarest, But regardless look on the left side of the stock band this is where ya will find the date it was made, look for a 1941 here (this was the last of the MK1) On the left side of the reciever look for the version ie; NO4MK1 or NO4MK1/2 or NO4MK1/3 or NO4MK2 the 1 is a straight mark 1 the trigger will be mounted to the trigger gaurd and it should have milled front sight protectors except for the Savage versions they were stamped, The MK1/2 is my favorite it is a MK1 upgraded to a MK2 but retains most of the MK1 higher quality items like milled parts etc... usually the MK1/2 has the trigger relocated to the bottom of the reciever this is better as it provides a consistant trigger pull a lil better than having it mounted to the trigger gaurd.
Your next one to grab is a Mauser, right now ya can still find Yugo 24/47s at a decent price and in excellent condition BUT they are starting to go up, The Yugo M48 never saw duty during WWII but is an excellent battle rifle the 24/47 was a 1924 Mauser updated in 1947 most saw WWII use and then got new barrels etc... in 1947 then were put in storage, heres the trick, DON'T go for the one with the hooded front sight, o.k why? well true that one most likally has a new barrel BUT if ya look for the ones that do not have a groove for a hood on the front sight ya will most likally end up with an original M24 barrel many of mine look to be new internally but they are all original barrels.
Look at The low cost Turk Mausers, they usually will be rough on the outside but exceptional shooters, pass up the K-Kale made ones for now and hunt for the Czech 98/22 the Turk rifles are contract rifles the Czech made were the best the 98/22 is what became the 98/29 the famed Persian mauser, It will be easy to spot and most dealers don't even know there are different Turk mausers so they all get the $80 price tag the Czech will have BRNO as part of the 3 line reciever ring stamping the other one to look for is the 1903 German made Turk mauser this one will be marked on the left reciever rail in a couple different fashions but will always me made in BERLIN the K-Kale rifles were actually made by the Turks and is a good rifle but not as rare as the other two nor as well made.
As far as Mosin's I know, the carbines are all cool but ya can't beat the good ol' 91/30 this badboy served right up to 1996 as a sniper rifle for several countries, Right now Classic arms has some super deals on the ex snipers as well as plain ol 91/30 ya need to get at least one hex reciever go for a stamped all matching and again make the bore condition your #1 priority
When it comes to milsurps BORE CONDITION is always your first priority, don't be intimidated by the infamouse "dark bore" as long as its got strong sharp rifling it can be brought back, to clean one up get some JB Bore compound either at Cabellas or order from Brownells, now got burn at least a hundred rnds through that dark bore then while its still warm start working it with the JB Bore paste usually a couple sessions like this will reward ya with a bright shiny new looking bore. Next all matching numbers if the rifle is to ever hold its value it needs to be all matching, some guns are expected to be not matching in the stock or bolt etc.. so do your research, for instance the Chilean mausers a matching bolt is a rare thing I've got several that are all matching but it weren't easy because ya see the Chilean govnmt stored the rifles in one arsenal and the bolts in another miles away to prevent unauthorized target practice at the presidential palace..... well gettin the two matched up again became an issue.... this was a common practice with many countries but some were better than others.... Now unless a rifle is a total beater ya wanna refrain from anything resembling sand paper gettin near it, there are many ways to clean them up without errasing the history hidden in the stampings etc... in the stock and handgaurds, reblueing, it will hurt the collector value and should be avoided but its your gun and your choice, the Turkish mausers usually have little or no blueing left on un-protected surfaces and they are fine will not rust as long as ya take care to keep em clean and oiled....
Good luck, a great source for info is to log into gunboards.com go to forums there ya will find collectors for each specific intrest, most of us collect gun based on eras such as WW1 or WWII or Korean or coldwar era etc... myself I've accumulated stuff ranging from the Civil war era to the present covering each area its taken over 30 years but there are currently over a thousand rifles in that part of the collection and a lil more in the handguns, sub guns etc... Don't over look the gear that goes along with each rifle, slings, ammo carriers and bayonets, they all add to the experience