Try Cruchfield. They usually have a nice selection. Or check out some boneyards. They usually have a crapload from various years & models on shelves.
Alpine or Kenwood....
Same applies to my Kenwood head unit (Not meant for inflight use). I have a couple discs loaded with MP3s. I can hit the right buttons and get what I want out of it before I leave home. It won't get touched again.All I can say is I have "about 3" of the "JVC ish" multibrand ones and one came in the 67. I like none of them. Small, poorly marked/ contrasted controls, you bump one and you are done until you can stop the car