There are two 1929 Bach Stradivarius Trumpets.
One of them is an early 1929 Bach Stradivarius C trumpet in the (Bb trumpet style) design.
Vincent Bach Stradivarius Trumpet stamped 1929 w/Case | eBay
One of them is a part missing 1928 Bach Stradivarius Bb Trumpet. (I think someone here should buy it!, It might go 500 dollars maximum but I think more around 300 in my opinion)
BACH STRADIVARIUS FACIEBAT ANNO NEW YORK TRUMPET #8xx - FOR PARTS ONLY !!! | eBay

With Faciebat Anno bells and the C trumpet would make you an Elite Rare Bach Collector. (Notice the unusual slide configurations)

Oh adding an intruder Rudy Muck Citation that may go low as well! Looks like an Early NY Bach clone.
Vintage Rudy Muck #1779 Pro Trumpet | eBay