I found a couple of factory keyless entry modules for my car but
OK, you FOUND them and they are for your car (like in your sock drawer)? Or you mean found them, like "I found them on EBay"?
These are vehicle specific. You can't take a remote for some other car and make them work on your car any sooner than take another 129 key blade and expect it to turn in your ignition. I mean, yeah one in a million or so shot it "may" work, but not too likely.
Why would someone tell you they are reprogrammable? UH, they want your money?