Yes. Unlocked iPhone models are very costly and I don't think no one would sell an unlocked iPhone for the cost you expect. May be you can get a network locked iPhone for low cost. You can then unlock it using remote unlocking service. You can get the remote unlocking service for an iPhone from OnlineGSMUnlock.com This method of unlocking an iPhone is safe, simple, affordable, quick and permanent. This doesn't require a jailbreak too.