I looked in NOS vendor Len Dawson’s catalog (dated 2004), but it’s not listed. To ask him about current stock, one has to Fax him or send him a postcard.
No listing in the copy of Bernbaum catalog, and I don’t relish the idea of phoning them to inquire.
I haven’t tried Napa or Jeff Carter yet.
There was a business in the next town called Hagen’s…they had everything from the '20s to '60s, but a fire last year wiped the business out.
If I can’t find one easily, I will probably add an under-dash switch.
I tried CollectorsAuto Supply’s online catalog.
They list the correct switch,in three different places…1 @ $50, 44 @ $40, and 22 @ ?, all NOS. (Shipping is $10-12 extra!)
1-888 772-7848. I’ll call them when I have some time.
Hey Roger,
I see them listed on pg 3 in a catalogue from Kanter Auto (Boonton NJ)
Ph: (973) 334-9575. www.kanter.com
They are listed at $27.00 ea
Roger - If you are talking about the switch that goes on the mastercylinder I get mine from NAPA. It doesn’t have to be Plymouth specific as long as the threads are correct. It hardly takes any pressure to activate the switch.
Dick.
Thanks guys!
Kanter, on-line, I amaze myself at how old habits die hard…I thought of Kanter but didnt have a current catalog, so put that thought aside. The oline listing doesnt SPECIFICALLY state they fit “Plymouth”, but it’s a definite possibility. Total cost would be $39.05.
I’ll see if Napa can come in lower than that.
I’d prefer to lose a little brake fluid installing in a replacement switch, than buy a modern switch, then have to fabricate a bracket and re-route the wiring. 
Andy Bernbaum has them listed at $12.50 for Item g-175
http://www.oldmoparts.com/g.htm
Item g-175
and I bought one from Napa years ago, I can’t find the receipt though. Not sure on the price or part number.
I have the Mopar Part number (1604989), but Bernbaum’s price is Rock-Bottom!
I guess I need to focus my attention his way!
Thanks! 
Roger - Does Birnbaums rock bottom include shipping?
Dick
Bernbaum’s wants $10 min for shipping.