I looked at becoming an RT examiner a few months ago...the CAA sent me a load of splurge - and also a flyer for some equipment. I cant remember the precise peeps who I spoke to but if you ring the CAA reception and get the bit of PLD dealing with RT exmainers they should be able to point you at some respectable equipment that they are recommending their examiners....
I would dig the info - but its buried deep in a 1.5' pile of paperwork!!!
Hope this helps,
Barry