I have reviewed all the partial ads from the 30s on here and looking at all the era Treasurers, I have not seen any mention of a 21j Treasurer. When comparing this watch to all the other Treasurers on this site, there is a distinctive thin rectangle that can be seen on all Treasurer dials (except the one with a re-dial) that borders the exterior of the hours markers. This can also be seen in the ad posted by Admin. The watch above watch features an incompelete rectangle that would bisect the hour hands if it was complete.
Size is not a match for this Treasurer model, http://www.mybulova.com/watches/1936-treasurer-5172
But could be a size match for this model, http://www.mybulova.com/watches/1936-treasurer-2305
The measurements I took were with a measuring tape in inches, which is the only means I have to measure at this time.