Its way hard because the chrome on those Schurmann rims tend to peel, then the rim rusts out. Its best to replace them with Puch skinny rims as they look very similar and tend to be in better condition.
I could build up a complete wheel if you want to go that way, but am figuring you're interested in all original parts. Oh, and the MP-9s had 11MM front axels too, BTW. Feel free to PM me on this.