Seamless tube is used in hydraulic system's,try a supplier for hydraulics.

I used 3mm wall tube for all my wishbones as thats what the stockist had others have too so if you can only get 3mm im sure it will be fine
Ray:)

wishbone tubes
 

hi thank you all you guys for the info i guess that my answer is 2mm for the tubes but im thinking of 3mm to be safer is that ok or will it be to heavy and they guy from kempton park i would like to buy the stuff but at the moment im having a bit of a money issue cause im jobless but i believe in getting as much info before starting a project it makes things a little easier for some people like myself