A. Spec II has Telefix fork braces for $129.95 to fit the 
1983 XV920 MK,  Brace No. FS81. They don't have images on their site, but you can see an image of the braces at the manufacturer's website - Telefix
Comment: The Telefix site is all in German, so if you don't read the language (neither do I), just click on 'Online Shop' and then 'Gabelstabilisatoren' (doesn't that sound like an illegal act?) then look at the right side of the page and see the 'TELEFIX Gabelstabilisatoren' or fork brace images. See? Gabelstabilisatoren is really not the strange new sex toy you thought it was going to be! *grin*