I don't know. A plain jane .308 bolt gun that you have to buy factory ammo for sounds awfully expensive for just plinking at 125 yards. Yes he will have plenty of versitility as he can probably find some factory 125 gr. loads all the way to 180 gr. hunting bullets. BUT HE DOESN'T HUNT! I have shot my 150 gr. FMJ reloads out of my Remington 700 VS and the accuracy was horrible. Once you shoot MOA with good quality ammo and then you shoot like 3"+ groups with surplus ammo, it will ruin your whole day.
Unless you want to start reloading and hunting, I just don't see how a bolt .308 is going to bring you much satisfaction. I would recommend the Garand or SKS for you at this point rather than a large caliber scoped bolt gun that you really won't have much use for. Now if you had a range out past 125 yards, it might be fun. But you can only shoot steel plates or paper at 125 yards for about ten minutes before that gets boring. No matter how long you are out there, it is going to be expensive.
So my new recommendation is:
1) Still want a scoped bolt gun, go .223. It will be much cheaper for what you are going to be doing. Even better, 125 yards is very doable with a .22LR and would be your cheapest route. Horrible for SHTF, but your best bet for cheap scoped fun.
2) Do not go over .223 for the scoped gun. If you want a "bigger" rifle than .223, get a semi-auto, iron sighted rifle. Low end an
SKS would be excellent as the ammo is rather cheap and they are a lot of fun (the first gun I ever bought for myself was a SKS when I was 17). Mid-range would be an
M1 Garand from the CMP. The ammo is going to cost you quite a bit, but you can't go wrong for SHTF in the PRK with a Garand. Next mid-range would be an M1 Carbine. Your ammo is still pretty high cost and the M1 Carbine probably has less punch than your Mini-14, but a fun gun. High-range would be a
Springfield-Armory M1A. The M1A is a .308 caliber best used with iron sights, but has the capability to be scoped and be quite accurate.
3)I just realized a new realm that I am not that much into, but would be fun. Get a .357, .44 magnum, or .30-30 lever gun. I would recommend the .357 because the ammo is going to be cheapest. Really the gun probably won't have a long range distance advantage over your mini-14, but it is bigger and you can scope those guns too. Check out
Winchester,
Marlin, or
Ruger.
The only thing that would change my recommendations if you plan on hunting or reloading. If you aren't doing either of those things, I don't see much point in you having a bolt action, large caliber rifle. It would be more accuracy and punch than you could probably use. Now a good lever action or semi-auto gun will be more fun and you can easily use it for SHTF. Really for an urban environment, what you have now is just fine. There are about a million different questions you really need to ask yourself about SHTF for your area, but those are best for another forum. Really the SHTF is a mythical event blown to fanatical proportions by us Internet junkies. So don't get this next gun for SHTF, get it because you want it, you can use it, and it will be fun. And if nothing else, use my list as a shopping list. I started it all with an SKS at age 17 and about 10 years and 18 rifles later I am still working on my list.