I just went down this road while looking for a gift for my father. He has many, many old 78s that he hasn't heard in years as well as a fair number of LPs. This was my choice:
http://www.esotericsound.com/turntable.htmI can't make any claims about audiophile quality since I don't have much experience in the turntable department, but I've never heard 78s sound so good. It's belt driven and everything you need is included for far less than the $500 you mentioned. The great thing is that with 4 different "78 rpm" settings, it covers all of those off-speed 78s that Alberporter mentioned and it makes a huge difference. It's easy to tell right away at what speed a song was really recorded, even if you don't know the song. You do have to change styli between 78s and LPs, but it's quick and easy, provided your eyesight isn't too bad. All I can tell you for sure is that my dad is enjoying his tremendously. Hope that helps.