To use up some of the time that has suddenly become available
, I've just been through the exact same process as Slymo. I couldn't find the narrower 8" linings either, so used the wider ones (SOK, Taiwanese?) and milled them to suit, made some collets for the pivot end (9/16, not 1/2", yes), and faffed about to get a decent fit. Plus made a new external lever for the thing to get a better angle than the revised arrangement offered. Slow job making a good square hole in steel, and working out where to orient it, but a pretty good result in terms of 'it works'. Meantime, the old shoes are off being relined, so there'll be that option as well. Plus got some 7" shoes which I hope will fit the rear when I get there, without all the hassle.