I am looking for a pot to replace in my Eico HF-81, as during shipping
it was damaged.
It is the "treble" double control pot with an on-off switch.
In the amp's manual it is described as:

Pot 500K ohm, linear, concentric w/SPST switch (18047 was the stock
number for Eico, but I don't think this interests you).

Anyone has one?

have you tried Mark Oppat? He has a pretty vast stock of vintage
controls. moppat at comcast dot net.

He also will rebuild them if, for instance, only the switch is bad. He
will need the specifications size and shaft style, whether it is tapped
or not and any other information you might have. The best thing is to
make contact then ideally send him the OEM part.

Peter Wieck
Wyncote, PA