Jim is right. I don't think I have seen more than a half dozen or so 1903s in 40 years. I once owned one that had a magazine with the three Cyrillic characters "O K Zhe" on the floorplate. (Don't have a Cyrillic keyboard, so I did a phonetic representation. "Zhe" in Cyrillic looks like two "K"s back to back, one reversed and the other normal.)
Apparently, Russia was the prime customer for the shoulder stocked 1903s.
Also, I think the inspiration for the 9mm Browning Long was the original .38 auto, as the dimensions are virtually identical with the exception of the length.