Try steamfittings or just about any of the ME suppliers eg. Blackgates, Bruce, GLR, Maidstone,Reeves, etc
Flanges you will have to make yourself or go to one of the German suppliers but then they would be threaded to suit 3mm pipe, though not many TEs used flanged connections. Infact you could make all the fittings if you were so inclined.
Edited By JasonB on 21/07/2014 07:31:18