Time for a quick progress update: the replacement Shopper bearing is in and working fine and the deck as a whole is working pretty well and certainly sounds very good. The only area I feel is still needing some attention is the step pulley, which is certainly the prime noise source on this deck now I've replaced the idler (the new one is way, way better). The step-pully runs fairly quietly as long as it's bearing holds oil, which unfortunately is not very long as it just leaks out of the bottom and ends up in a pool on the wall shelf. There's another small pool under the Shopper main bearing, so better people than I can't make these things oil-tight either... old decks, don't ya just love 'em! I should be able to fix the latter with a light smear of grease on the gasket next time I can be arsed stripping the deck right down, but the step-pulley bearing is more of a problem. I'm on the lookout for another step-pulley, ideally I'd like to find one in true NOS condition.
I've not got round to trying the lightbulb trick yet I want to build a mains block type affair for that, e.g. a simple plug-board with two sockets, one wired in series with the other it has to be the neatest way of doing this, though I've yet to find a suitable two-way donor board. I want something like a two-way version of the old grey Music Works 6-way block, i.e. something I can just screw a pair of standard single 13 amp mains sockets to. I'm expecting this to make quite a radical difference as the step-pulley noise is unquestionably connected to my having to use the eddy-current brake almost full-on to slow the deck down to the correct speed. When allowed to run with the brake at it's lowest setting the drive mechanism is all but silent, though it's probably going round at about 36rpm!