Had the same problem and fixed it with epoxy glue. I used the soft rubbery type epoxy not the stone-hard type, this type will crack when you try to refit the screw.
Drill out the hole to 6mm, fill it with glue and then drill a 3-3,5mm hole to refit the screw.
This worked for me (twice!!!!! with two different footstraps on my Futura 133)