In reply to Ben_Climber:
Make them yourself from the off cuts - there's nothing special or hard about this (mainly sand them to remove splinters and sharp edges), I've got lots made like this from odd shaped off-cuts. Use a hole-cutter to make pockets.
Unless you are after a particular aesthtic don't bother trying to route slots for fingers (like a beastmaker) it's quite tedious - better just to assemble the edges you want from bits of ply. Ditto campus rungs etc - don't get too worried about reproducing the shapes being sold - just make your own.
If you want to texture it, (sharp) sand and PVA works well and doesn't stink like resin based texture (but let it really, really, dry first and then brush it to get rid of the loose stuff before use). If you're using crap quality ply the PVA on its own is pretty good for making it strong and dealing with the tendency to peal and splinter.
An hour with a drill, table saw, belt sander and a basket of off-cuts will have you more holds than you know what to do with - enjoy!
