The Seiko was the same as the Consew 757R-1 I believe. Consew later replaced it with the 757R-3 . Different feet. The feet that came on the Seiko SH-8B same as on their older flat bed. The only feet I can find are the 28472 and 27471. To make a left or right toe foot will mean remove toes and grinding the feet. I could find no other feet for that model machine.
Try these Consew numbers: #22859, 22860, 4410143800, 471015100. Good luck!
glenn