Royale o-ring list (sanity check)

Sorry for bring up YAORQ (yet another o ring question), but I have lifted the orings from the FX parts diagram and tried to make note of what the o-ring actually does. Can anyone double check this and confirm what one oring does that I can't determine? It's the 2nd one in my list below (D9).

http://www.fxairguns.com/wp-content/uploads/2015/10/Royal-Drawing-and-Partlist.pdf

C4 19098 O-ring 18x4 NBR90 (shroud area)
D9 - X 5112 O-ring 5,28x1,78 NBR70 (??????)
D17 5105 O-ring 9,3x2,4 NBR90 (hammer spring area)
D19 2529 O-ring 4,3x1,5 NBR70 (breech seal)
D20 2528 O-ring 1,5x1 NBR70 (probe seal)
D24 HP 5111 O-ring 2,5x1,5 NBR90 (hammer spring area)
E1 – 5,5 5108 O-ring 5,28x1,78 PUR70 (regulator area)
E2 5112 O-ring 5,28x1,78 NBR70 (regulator area)
F4 1504 O-ring 4,42x2,62 NBR70 (rear of probe)
G3 4528 O-ring 7,66x1,78NBR70 (bottle fill connector)
G4 19088 O-ring 15,88x2,62 NBR90 (bottle fill connector)
G8 5107 O-ring 2,9x1,78 PUR90 (bottle fill connector)

And if anyone can map these orings to specific vendor part numbers I would be most appreciative!

Thanks!
 
OK, I'm a dummy and here is a correction...

The parts diagram in originally linked to on the FX site is an OLD Royale without a regulator. Trevor from Utah Airguns confirmed that I need 2.4mm CS X 11.6mm ID Metric Buna-N 70 O-rings for the regulator. 

https://www.marcorubber.com/o-ring-size-chart-metric.htm

English size of regulator o-ring:
.094 CS x .457 ID x .646 OD 
 
 I ended up getting a bag of these on Amazon I believe, they work just as well as the factory ones.

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