My last trip to a local goodwill and finally something although it wasn't a boombox it works in conjunction with my boomboxes. It's a Luxman K-105 autoreverse cassette deck! This Luxman has the quietest tape mechanism I've ever heard, there's no clicking, clunking or clanking for any function it just very quietly performs the function. I've never heard fast forward or rewind that was nearly silent until this one.
The scoop on this one is:
http://www.vintagecassette.com/Luxman/K-105
This was a $600 retail deck from 1985 to 1990

The scoop on this one is:
http://www.vintagecassette.com/Luxman/K-105
This was a $600 retail deck from 1985 to 1990