Not *exactly*. The Tandy 3 was a rare "OEM" version of the Model III intended to be sold through third-parties. Here's a video featuring one; their unit was supposedly sold through Taranto Associates, which was a company that sold turnkey accounting software bundles. (They were a regular advertiser in 80 Micro, and I'd swear I remember one of their ads actually featured a Taranto-branded Model II.) They did a similar thing with the Color Computer, calling it the "TDP-100":
I actually had a TDP-100 for a while (got it at a garage sale in the late 1980's, long gone of course) so I guess they weren't *that* rare, but the Model 3 is apparently... rarer.