Cheap solution found! Our topping lift was really stiff to haul up, not good. It goes From the top of the mast, under the boom through a bullseye fairlead, back up to a cheek block at the top of the mast, then down to the foot of the mast; we wanted to lead it back to the cockpit but it was not at all good.
It seemed to me that most of the resistance was caused at the boom, so I got some cheap flexible plastic tubing, put it through the fairlead and stopped it sliding out, then threaded the topper through it. Result! The rope slides easily through the tube and the topper works as it should, even from the cockpit. It cost about a squid, and also saves friction on the sails where it once rubbed. One happy saily here