Avoid arcadewarehouse aka arcadewhorehouse like the plaque. They are renowned for ripping people off, especially those new or inexperienced.
Mo @ Videotronics is a good guy though, I'm sure he can sort you out.
If you want a candy then Jeff @ Digital Systems Designs may be able to hook you up, his website is
www.digitalsystemsdesign.co.uk His site is quite new though and he doesn't have everything listed yet.
There is also Craig at
www.giz10p.co.uk, I think he sometimes has surplus cabs in.
www.jammaplus.co.uk may also be a good source for a wooden shell.
I live in Lincoln myself which isn't a million miles from Leeds. I have a few arcade buddies in Leeds/West Yorkshire area so there is definitely plenty of us about