This set is actually from 1939. The Westinghouse sets, like the Silvertone sets, were all built by RCA and all use the same chassis. RCA designed different cabinets for the Westinghouse and Silvertone models. These sets were never sold to the public and made strictly for display at the Worlds Fair and for promotional use by Westinghouse and Sears. Afterwards, most were recalled and many were rebadged as RCA. My Westinghouse WRT700 (RCA TT-5 variant) was rebadged "RCA" while my Silvertone 7272 (also a TT-5) was not.
There were about 250 total Westinghouse sets made of the various models and about 50 of the Silvertone:
http://www.earlytelevision.org/us_sets_made.html
The crt mask is the same for all three TRK-12 variants. The ones Barry has were made by Ed Schutz (the guy who does the VT71 masks) from a perfect original I had and they fit very nicely.
Darryl