You might try for the VW version of the switch new at VW Classic Parts, or repro from VW Bus Shop in Germany, or GoWesty,Bus Depot, Van Cafe (or whatever they're called now in CO), etc. here in the USA, & TheSamba.com.
IIRC the same 4-pin switch was used for that era Bugs, Buses, Squarebacks, 411/412, Ghias, etc. - somebody must be making them repro, or VW Classic on re-releases.
Tom
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