Hey Dave,
I like that you want to make them from wood. Less plastic! 
If you had a cnc machine you could also mill one 
Unfortunately I did not find the time to make these measurements yet, but Bill @Machinist makes very nice plans, on this one, there wasn’t much that was missing and that he would have measured the holes of the rails. Perhaps he has a plan of the whole foot cross section?
Thank Bill @Machinist for this
(excerpt from a file from Bill that I downloaded once a while ago))