Say Mike,
Just contact the good folks at Aristo, they've replaced two total switches for me so far and about 3 of those micro switches on other units. Just explain your situation and they should do the same for you, only cost might be to ship them the old part if they request it, however that only happens usually if it is a whole switch as two of mine cooked/shorted the screw connections to the track and melted the cross ties completely. They just totaly rebuilt my GN Mallet drive units and two SD-45 drive units and completely replaced two others, those folks are great....
Byron
I've replaced them with Radio Shack. (left a note on the Aristo Forum at the time) I'll look and see if I've got the number.
Same micro, manufacturer and part number as the original Aristo.
You might take the old one to Radio Shack and match it up.
Don U. TCA 73-5735
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