Does anyone know where I might be able to purchase rubber bushed rod ends, preferably female so I can just use a length of stud and locknuts to make an adjustable engine steady bar? Can't seem to find much at all.

Something like the ends on these

http://www.racingbeateurope.com/bmazda-mx-5-99-05-racing-beat-roll-bar-endlinksb-1765-p.asp

google turnbuckle linkage also have a look at mcgill motorsport they do rod ends and various bits to make your own

Ah! that's what the proper name is! In that case I'd rather use male ends, would look much better and probably be stronger.

McGill do lots of rose joints/rod ends but haven't seen anything that would provide any damping

worth giving mcgill a call. they are near me and very helpfull, just cause its not on their site doesnt me they dont have or can get it for you.