Hi Bob,
When you say "present-day relationship," does that mean there was a known past relationship? If so, what was it back then? Bill Cook made a passing comment about it several years ago, but he didn't explain quite what he meant.
The Japanese manufacturers of Swift products were not exclusive to Swift. Hiyoshi Kogaku, for example, made Type 2 products for other vendors, although none were in the 8.5x44 Audubon format (to my knowledge).
Ed