In message , MoiInAust
writes

The British Vintage Wireless Society (BVWS) has a regular magazine. I'm sure
their members would be interested.

In the right quarters, those valve testers are quite highly prized.
Very, very few 'ordinary' UK radio amateurs would be interested - unless
they had an interest in vintage equipment. The BVWS seems by far the
place to ask.
--
Ian