Figure on some machining or a steerer tube modificaiton of some kind. I picked up a girder fork from an AJS a few weeks back. The top clamp is just shy of 1" so that will need to be milled out. I did not get the steerer tube but i think it will be relatively easy to make one with a lower link attachment point, kind of like a schwinn springer steerer tube.
I think modifying these forks to fit is reasonably do able, but certainly anticipate some creative thinking.
The damping and rebound will be heavy for a bike but hey, if you like the look, go for it.
BTW: I picked mine up from a motorcycle junkyard about 15 miles away that specializes in 1980's and older. I bet they have 30 of those moped forks right now. the place is called Coopers in Franklin NH, you can google it i'm sure, they will ship.