Does anyone know where I can get a 2nd hand unit?
I've found one in the US but it's as dear as poison. and the exchange rate isn't helping either.

Why do I need one? 'Cos I broke the one I have ... by ... trying to unseal it to clean the inside of the glass. Actually it cracked and one half came free in my hand. "I know. I'll use some glass repair epoxy to mend it

Cheers.
HF