I think the frame widths might be a little different, which would suggest axle length differences. But even if so, can't be much?
I recall some discussion here about a year or so ago about someone substituting (or having the idea to substitute) some stainless steel bar stock as an axle replacement. Of course, you'd have to get it the correct length; hacksawing SS ain't gonna happen.
Perhaps someone else here will chime in or can measure the axle length of their recent Performer. You sure yours is roached/can't be saved?