There's TONS of options for bolting onto the windshield hinges!
(Can't really recommend anything though - I have mine perminantly mounted on the doors and side mirrors aren't required for my State - so I just don't run 'em when the doors are off.)
Here's a Quadratec search. I have it narrowed down to the YJ-campatable ones for ya'.
Mirrors - Quadratec
Thought about getting some actually... But I'd have to get new doors or deal with my YJ looking stupid with two sets of mirrors. Haha! Figured I'd just save the money.