With that sunroof cracked open like that, I'd be darn worried how much has been funneled into the interior as well. As with most things, the value in this one sits somewhere between $1k and 5k - maybe it's been covered and interior is minty and looking underneath reveals the pristine undercarriage and zero rust, but also maybe you can reach into the interior from the wheel wells and interior is wrecked making it worth nothing.
A perfect illustration of the downside of living with a Supra in Texas. The sun has baked every piece of plastic, rubber and vinyl, i.e. all the trim parts that are unobtainium. The interior is probably just as bad. Sure, you could get it running and driving again, but without a miracle, its never going to look good again. The only such miracle I could imagine, is perhaps somebody up in the rust-belt has one swiss-cheesed with an immaculate interior and at least the upper trim all intact. There's a source for fiberglass rocker moldings and we've got a couple of people working on trying to reproduce the side moldings. But the car is a thousand miles south of probably the southernmost such rustbucket and the economics of a restoration don't work even if both cars were free.