I would imagine it's in the hands of his wife and/or daughter.
Terry was my first guitar hero. Don't know why the others slipped through the cracks. Maybe because I played trumpet in school and was drawn to Chicago?
There are a lot of folks out there that love Terry's playing, but I don't know that it's widespread enough that they'd jump on a signature guitar. It's an odd one besides. Essentially a pickguard-less mongrel w/ PAF neckbucker, a chopped in half Tele bridge front joined to a Strat bridge and a bunch of stickers all over it. Has anyone ever seen the back of that guitar? I've never seen a picture of it with a whammy bar on it so I've been curious as to whether or not the strat bridge was fully functional.
I'd thought about maybe making one myself one day (sans the strat bridge), and I did find a page from a guy who's in the process of doing it himself. I'd want to find some vintage Pignose stickers to use on it (Terry had all he needed, obviously).
http://www.geocities.com/pdga14567/terrykath.html
Dang, the more I think about it the more I wouldn't mind having Fender do something like that. As long as it didn't cost an arm and a leg.