If you are looking for some spring powered, bolt action airsoft sniper rifles with scope, then airsoftsniped.com is a great place to check. Not only do they have tons of bolt action airsoft sniper rifles with scope for sale there, they also have plenty of airsoft sniper guns with scopes and bipods too (or without scopes, if that is what you are looking for). Airsoftsniped.com also offers a pretty good return policy, and they have reasonable prices, and pretty good customer support.
Some other great websites to buy airsoft sniper rifles with scope and bipods are sites like airsplat.com and pyramydair.com. Both of those companies are actual distributors of airsoft guns, so they have pretty much unbeatable prices. Amazon and eBay.com have a lot of airsoft rifles for sale too, so perhaps you may want to check them out as well. Just be sure that you buy from a seller that offers at least some sort of return policy.