A local cash and carry sells those cooking pans. They supply to a lot of the local Indian restaurants here.

If you're in london head to brick lane. There's taj stores, bangla city, bangla town and another shop off brick lane which sells these pans. They seem to generaly just have small pans but they're the ones used in the takeaways. They're very cheap, maybe ?7.
Stainless steel is a bad conductor of heat - you need another metal as a base of the pan to make them work properly. This is usually iron or aluminium and is what they use in more expensive pans (le creuset, jamie oliver's ones etc). Lots of shops sell pure stainless steel pans now which is basically a con which they get away with because of lack of knowledge. Ikea pans would be a good example of a complete con.
BIRs know what they're doing which is why they use the aluminium pans. Iron pans  are good too, and cheap. BIRs use these as well (karahi/balti pans).
It's best to buy equipment at asian supermarkets IMO as they dont rip you off.

Hi All

read all the posts and watched the video, I have in the past worked in many a BIR not as a chef may I add but seeing as my father was a chef a lot has passed on to me, and I love cooking inc curry, right back to me working in the kitchens, I was a refrigeration engineer and as a lot of the work involved being there for 2 to 4 hours I saw a lot of what went on and believe me each chef in each BIR had his own way of doing things, yes lots of things where similar but I doubt if 2 where exactly the same, re the aluminium pans as stated best to buy in Indian shops and the reason they use them is cheapness and it's what they are used to in India by pure luck they also work well for what they want, BIR kitchens tend to be small with a table in the middle the cooking ranges (normally second hand) big old cast iron ones on one side and the refrigeration on the other side hence why I saw and learnt so much.

frdgedoc,

thanks for adding the extra context. my interest is most down to the cooking but the background to it all is always interesting and i guess part of the attraction.

the link was particularly good for me as although i've watched it before at the mo i was interested in how to cook my tikka in the UB fashion (read semi pro and back garden tandoori post). i thought i read/seen to leave thye chicken in big pieces for marinating and cooking (as opposed to my norm of cutting up into pieces). this is what i've now done for my 1st attempt with my new skewer.

best wishes.