Musky's right about the bridges - this seems to be a flaw on a few early 80s Matsumokus with 3-point bridges, but they are interchangeable with any 3-point design so finding a replacement (if necessary) shouldn't be a problem. This is mine when I got it:
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On a bass like a Track 4 I might feel inclined to replace it with something like a Hipshot Supertone or the new Babicz 3-point.
Pickups were DiMarzio as standard, again something found on a lot of Mat basses at the time, should be wired for series/parallel switching which makes them quite versatile. Cream covers should be standard, you can check authenticity by hex key size (DiMarzios are imperial) or wiring colour, which will be white & green/black & red.
The Ebay sale at £190 is an indication how far vintage MIJ prices have fallen in the last few years, the Track 4 is pretty high spec (set neck/carved top etc) and 5 or 6 years ago £350-£400 would be more usual for a good original bass. These are actually pretty scarce, much less common than the single-pickup/bolt neck Track 2 like mine.
Jon.