Thanks very much "Caveman" I have ordered the aluminium one. First time I've used the forum-new at the hobby/obsession, as I'm sure was guessed-and thanks to every one who has helped, excellent.
Cheers, Roger.
Thanks Malcolm for your helpful suggestion, I found one in the USA, but the sites is a few years old-anyway I've emailed them.
Can you recall where you got yours from?
Regards, Roger.