DD-214 in hand and I'm gonna party like it's 1998
The Bell 206 was type certificated under CAR 6 in 1964, before there were FARs for signing off new aircraft, which is bureaucratic mumbo jumbo for "grandfathered in on lots of stuff."The FARs changed markedly after the 57 and again last year. The 57 still wouldn't cut it under today's standards.
I don't know how much the TH-57 was connected with that (I figure you might, what with your current gig) but I always assumed nearly all of the 57A paperwork was cut and paste.