For service parts like brake shoes, pads, cylinders etc, I tend to look out for NOS, even if it's non genuine. I have brake shoes for my Datsuns on the shelf and they are usually Ferodo, Mintex or similar. Usually you can pick it up off of ebay cheap and stash it away until you need it. A stock of routine service parts doesn't take up much space and if you are buying casually when you don't need it, you can wait until it turns up for cheap. The older stuff tends to be fairly decent quality I've found. Brand new non-genuine replacement parts are a last resort because of the quality gamble.
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