You may want to try a Benjamin Discovery in .22cal. You can use open sights or a scope, you can use CO2 or high pressure air, however, the price is a little higher than you quoted (the Discovery is about $250 for just the gun and about $399 for the gun and a hand pump and no recoil.
Spring guns cost less, but there is a learning curve to be able to hit center target. They are also known for breaking scopes, as there is a "double recoil", they recoil forward and reverse, hard to keep zero'ed, etc/. unless using an HW30S or a HW50S. MAKE SURE the model has the "S" in the model. With the "S", you get the top of the line trigger, as it is adjustable, however, both models of guns are top of the line, great shooters, I would not consider them "hunting guns". Both seem to do better with .177cal.
Be aware of GAMO. They are cheap, overpriced, heavily advertised and made to sell. Claims of up to 1,500fps are not only exaggerated, but even "IF" they did shoot at that speed, pellets are NOT designed for that speed and hitting a target, consistently would not happen. IMO, 930 - 950fps is about perfect for hunting, however, with a pellet gun, you should concentrate on FPE (energy), as that is a MUCH better "ruler" of what you are getting. As an example, say a GAMO rifle is advertised at 1500 - 1600fps and let's say they actually shoot at that speed. In order to do so, a light weight "specialty pellet" would have to be used, say 3 or 4 grains. 1,500fps "sounds impressive" until you realize the energy is 14.99 fpe - 19.99 fpe for a 3 grain and a 4 grain "test pellet". It will sound like a 22lr rimfire being shot because of the sound barrier being broken, which in turn makes the pellet VERY INACCURATE and a waste of time and finances.
On the other hand, with something like the Discovery (using high pressure air), you can shoot a LOT more accurately at 850 fps and using a 16 grain pellet, get 25.68 fpe, using a .22 pellet instead of a .177 pellet. A (.22cal) pellet, larger diameter plus a MUCH HEAVIER Pellet moving at a speed under the sound barrier will make for shots hitting where you are aiming, making accuracy, shot placement, so much more reliable as well as a much more actual humane varmint kills.
Next to a GAMO, the Benjamin Discovery is so much easier to shoot, accurate, you can use high pressure air for hunting or CO2 for 100's of shots when plinking, etc.
I started with spring guns, however, there are so many cheap made "springers" on the market, you really know what you need to look for, the problems they can create, that a high pressure air gun is a MUCH better choice. Sure, there are good springers that will shoot where you aim, such as an Air Arms TX-200, but you will pay for one, a LOT more than a GAMO. BTW, stay away from the newer Webley's and BSA's as GAMO own's them now. If you can get an older, used model, not made in China, Turkey, etc, they "were" GREAT GUNS and high grade guns, however, you also paid for the QUALITY of a British built BSA rifle, but notice, high end air gun stores are no longer selling them. (There is a reason for that), after so many are defective, do not shoot correctly and returned, it is no longer profitable to sell them.
Now, if you just have your heart set on a "springer", this is a good buy on a factory refurb. I only recommend you get a better scope and a one piece set of rings/mount and you would be MUCH MORE SATISFIED than with many other cheap air guns. Here are a couple of links. You can search the pages and also find the discovery there- (you may have to copy/paste links)
Refurbished Benjamin Titan™ NP (.22)- $80 Link-
http://www.crosman.com/outlet/9-BW8M22NP
Sell the scope and rings and get a better set-
For the Discovery because there is no recoil, I would recommend the-
Tasco-Varmint-2-10-x-42 with Mil Dot and Adjustable Objective. AO is needed on any air rifle, IMO. $60.39 minus the $20 you sold the 4.32 non AO scope and rings for and you are down to $40.39 for this scope!!
http://www.walmart.com/ip/Tasco-Varmint-2-10-x-42-Scope-with-Mil-Dot-Matte/5684942
For the springer rifle, you will NEED a scope built for a springer's "double recoil", such as this one-
CenterPoint Illuminated-4-16x40mm Scope with A/O for $67.32, and again, after the sale of the 4x32 for $20, you end up paying only $40.32 for this scope. It is always in stock in Wal-Mart, but not always online
http://www.walmart.com/ip/CenterPoint-Illuminated-4-16x40mm-Scope/17173797
Both scopes recommended are 1" tubes, so, you will need the medium mounts. DO NOT skimp on the mounts, it is not worth it and will be a big PITA trying to keep the scope zero'ed without something that holds onto the rail.
For $16.23 you can get a good set of mounts/rings (for their purpose). Medium height, 2 screws per mount for a total of 4 screws holding the mounts to the rail, 4 screws per ring to hold the scope tight, for a total of 8 ring screws holding the scope and 4 more screws to hold the mount to the rail. These rings also have "tape" on the inside to keep your new scope from getting scratched and more importantly, to keep the scope from moving at all.
http://www.walmart.com/ip/Centerpoi...bucket_id=irsbucketdefault&findingMethod=p13n
So, in the end, you would have a total of aprox. $135 for the springer, scope and rings.
For the Discovery, it would be a bit more, however, like most guns, you get what you pay for.
Air guns have come a LONG WAY in the last 25 years or so and continuing to amaze us air gunners every year!!