Yeah. That's a rare bird you've found there. The Tandy 3 is an "OEM Labeled" TRS-80 Model III, and they are indeed extremely uncommon. It was a version designed to mostly be sold through "vertical marketing", IE, through consulting companies or whatever that packaged the computer as part of some kind of "business solution". (IE, they preloaded it with expensive custom software, provided training, whatever.) They also sold the Model II that way, but I think those might actually be more common. (And less unique because I'm pretty sure those were the standard silver case color, they just came with a generic badge that sometimes the reseller would replace with a custom one.) If more than a couple thousand of these ever made it out into the wild I'd be surprised.
If you're feeling lucky you can plug it in and flip the rocker switch while holding down the "BREAK" key, if it's healthy you'll get a "CASS?" prompt on the screen. (Powering on without break will cause the drives to spin.) But if it's missing screws it would be understandable that you might not want to go there. You probably also don't want to open it, it's *very* easy to break the back of the CRT if you don't do it right.
Anyway, I'm sure you'd be able to find a Tandy fanatic willing to take it off your hands. I'd give you a couple twenties for it, no questions asked, but I'd probably be robbing you blind.
