way up here on the west coast of Canada, a few of us have been pursuing the sup/surf foil dream. Not much used gear up here and we're all too cheap to buy new, so there's been lots of DIY'ing. For learning, any cheapo mid size sup would work. We started with through hull holes, with golf club shafts glassed in. Now installing fin tracks, basically two longboard boxes in some high density foam. You can also buy a stick on mount or suction cup mount (remora), but they seem way too expensive relative to some epoxy, pour foam, and a couple fin boxes. I started sup foiling on a 9.6, which I found out pretty quick is way more than you need. I now have a 7.6 door sup that works great. I made a 6.0 sup foil barge, which may have crossed into too small. However, for wing foiling, I just installed foot-hook mounts in it, and I think with those it may be an awesome wing foil board, we'll see.
So the answer is yes, most any board will do ... if it catches on, you can invest in something more refined later. Surface sup riding is an ok way to start out too.