Turbo oil feed

[Phaseone]

I removed this yesterday because A. The oil pressure gauge doesn't work and B. there is an oil leak from the general direction what i want to know is, is there supposed to be a non return valve here somewhere?
16701

[Phaseone]

And is this the flow restrictor? i have a roller bearing turbo and i have read that it should be a small hole? This looks to me to be about 2 or 3 mm at the bottom
16702

[NRG]

None return should be on end of hard pipe before it feeds the flexi hose.
Fitting in turbo looks right.

[NRG]

EBay 160736948987

[Phaseone]

Cheers dude:D