Shop around. I never pay top dollar for anything.
I can get that Springfield XD I am considering for under $500. Of course it'll be over that with tax, shipping, and transfer fee but that's to be expected.
I have a Ruger P-89 that I am debating what to do with as my confidence in my ability to use it effectively has been destroyed. It costs less than $400 brand new and would serve anyone for a lifetime.
I have a 686-2 I paid $325 for. It's in good enough shape to fire another 30k rounds. I will probably have it rebuilt by the Performance Center some distant day but it doesn't strictly need it.
I have a brand new 642 that was $310 out the door. No, I don't feed it a constant diet of +P ammunition but I have 600+ rounds through it and it is none the worse for wear.
Hell, for $200 you can get a brand new Rossi. I'd carry a Rossi into the worst situation imaginable.
If self defense is your goal there are lots of excellent options under $500, especially if you like revolvers and don't mind used guns.