I have been involved in ladder making before. It is a lot of hard work and probably not worth it for most clubs, since you need to build quite a lot to get any kind of economy of scale. For example, you have to buy a big reel of wire to get a good price and that will make several ladders. Same goes for the resin - industrial sized vats of the stuff reduces the unit price considerably, but it's no good building just a couple of ladders.
Electron ladders are also used for sailing (you hoist an electron ladder to the top of the mast using one of the halyards to facilitate climbing up to fix equipment which is up the mast). I guess they have some applications in industrial access, since various suppliers of that kind of gear sell electron ladders.
Electron ladders regularly come up for sale on eBay. If you're in the market, keep a lookout!
Mark
P.S. I LOVE caving on ladders. Juniper Gulf anyone?