500 bucks for a Mustang? You gotta be crazy! No matter how old it is or who splooged on it, it's a piece of junk. Always was, always will be. For that money there are a million things out there that play and sound better.
Hmmm... I'd play that bass any day and I make all of my income from music. Your opinion is your own, but it doesn't hold true for everyone. I love the old Fender short scales! And, the Squiers from the 80's(especially JV), are better than almost any 70's Fender out there build wise.