I would suggest you look at Pin Map, and go to some local places that have pinball. More often than not locations will have 90s Bally/Williams or modern Sterns, which are out of that $3k price range, so try to go to places with a large collection, as they're more likely to have the older stuff. My suggestions:
Blackout
Firepower
Gorgar
Scorpion
Black Knight (might be hard to get in your price range but if you're patient or are cool with a player's condition game it can be done)
Paragon
Pinbot
Fireball
Galaxy
Meteor

and fuck the Gottlieb haters, I would suggest
Mars God of War
Devil's Dare
Black Hole

As for EMs:
Mars Trek
4 Million BC (dinosaur themed, not exactly monsters)- for an EM this one is pretty loaded. Zipper-flippers, skill shot, multi-ball