Go to Vortex Power mate. Terry is very helpful and the Boostlogic line of parts they do covers your needs from every angle as far as the mechanical side of things is concerned ie Turbo, manifold, wastegate, injectors, piping, filters etc. Saves you a lot of time and headaches searching around different places for bits and bobs on your list.
As far as fitting goes, Phoenix are just down the road and Mark there is a top fella and mechanic to boot!
In fairness and with all due respect to them, I havent tried Envy, MKivStore, Chris Wilson or Whifbitz for their fitting skills (although I hear good things about them all), but they are very reliable for parts and can almost certainly get whatever it is you need and offer very good technical advice. This I have tested.
As for the others, dont bother.