Guru help needed brakes body number

OK a couple of questions here.

Plate number, i have a parts book that shows a plate number of 38 /39 or 40.
by body number ends in 40, am i on the correct Tack or ???

Brakes,
my drawing shows Two springs in the master cylinder, the large one and the smaller one at the end.
Having pulled down my master cylinder (F) i only have the one spring though every thing else looks complete. did the PO miss something or is there another version??

Is it is needed, are both springs included in a valve Kit?

Looking at part numbers for both master cylinders. they being different? are the actual master cylinders different? if so how. I have not been able to locate different seal kits giving me the impression they may be the same.

Lastly and obviously it would be better just to get new master cylinders. where who and is there options IE better other models etc.

Thank you in advance…. Dean

Think the kits just have the rubbers in them , not sure what car your talking about , but a new Master cylinder for a MK2 is around £200 at SNG , or a few on e-bay from £100 down to £50

OPS 61 Mk10 3.8 typing more to make 20 characters.