I have the original bases. A little tired, but serviceable. I have about half a dozen plastic lenses, some new in box, some were good used, and one or two which have a bit of scuffing.
Someone has patterned these, but they come with plastic lamp holders, and the lenses don't have the Lucas legends on. Haven't seen them up close and personal so to speak, so can't vouch for quality, however if not too expensive, they may be worth having for the rubbers.
In two minds whether to use the 3" or go with the L488 glass units, which are common as muck and I think look nicer anyway. The 3" units work better with the LED units I tried, as the lamp sits up higher in the base and thus the side mounted LED's do the work they're supposed to.