I recently bought a penny farthing from http://www.standardhighwheels.se. The specs for these bikes have been tweaked (improved) slightly and the website has not yet been updated to reflect that. So when the bike arrived one of the improvements was dual hole 125/150 square taper (cotterless) cranks. I was expecting only single hole 150mm cranks. In addition to the extra hole, they are nicely finished, handsome looking cranks.
It immediately occurred to me that these would be pretty handy on a couple of unis that I regularly ride that still have this crank interface, including my 36" UDC Trainer/Titan. My plan had been to take them off the penny and transfer them but I sent a quick email to Per-Olof Kippel (who runs Standard Highwheels) and asked if he could sell me additional ones even though they are unlisted on their store.
He confirmed that he could and that they intended to list them on the store in the future. For two sets of cranks (i.e. 4 individual cranks) he charged €64 (€32 per set) and €10 shipping (to Norway), which I think is pretty reasonable. Of course he might have given me a deal as a previous customer, so anyone else interested should confirm this price for themselves. From the invoice I was given the product code for these cranks appears to be “3133”. I include a picture so you can see what they look like, for anyone else here who might be interested in upgrading their cranks on any unicycles they have that still use this interface.