On 7/15/2018 6:56 PM, trader_4 wrote:
....

That's Underwriters Lab, which means it's UL certified. It has nothing
to do with who make it, which is Leviton. I seriously doubt it's a
custome part, it was probably a common Leviton switch at the time, no
need for anything fancy for that application. The key things are the
mounting hole size and that space is not tight behind it. In which
case you should be able to find one that fits. Hole is probably a
standard size, you could ream it out if need be I guess. It also
needs to be rated for 125V, 3A or higher.
....

It's not that there's anything special about the switch itself, it's
just that they're often not made except for OEM applications and thus
not available elsewhere as standard Leviton catalog item...

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