This dovetail is heavier duty than most vixen dovetails and has a much wider attachment surface .Length = 470mm, with 70mm wider contact surface for attachment ,this one has a few more holes drilled in it . see link below
https://www.baader-planetarium.com/e...mm-for-sc.html
These cost about $120 without post new. Asking $70 postage included for eastern states.
Philip