I seem to recall a single digit number being thrown around as the production number. I'd be surprised if they made so few having gone to the trouble of getting set up for one, but then who knows. I think a lot of records were lost when Supra changed hands, too. I suppose Lane here might really know, but it's almost certainly fewer than 100, quite possibly fewer than 10.
I'd say the odds of finding one without the internet would be about zero. But it's almost just a matter of time if you cast a wide enough net on the interwebz these days.