Does anybody sell the Dash lamp dimmer switch for a 70 challenger with a rallye dash? Thanks Guys.

You mean High Beam Switch.

Nothing special about that switch. Plug was same across many years/models.

Sorry I am talking about the dash lights dimmer switch.

Vans Auto has reproductions. I'd consider having an OEM rebuilt (member devinism does that) before buying a repop.

https://vansauto.com/product/interior-dash-dimmer-switch-70-74-e-body/

They are notorious for going bad.
Surprised no one has designed/offered an improved sudo-replacement for them.
Something other then rebuilding one.
Doesn't carry much power at all.

Once removed from the dash cluster, dash-lite dimmer control is EZ to troubleshoot.
The majority of problems are due to the rheostadt windings being dirty, after 50 years..
Clean with some spray contact cleaner like Deoxit, let it dry and then very lightly coat the exposed wire windings with dia-lectric grease. Also now is a good time to make sure the contacts have enough pressure on the windings.
Since the OE dash lites are dim to begin with, one thing I have done on many Mopars is to put a short jumper wire between the rhoestadts' contacts so basically it is bypassed and the full 12V goes to the dash lites.

Just my $0.02...

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