single red 1680 MK1

[scooba]

I purchased a single red 1680 mk1 with the serial number 21863xx from references I looked up it appears it was manufactured around 1969 ,The sales invoice dates it first sold in 1972 ,I'm sure from memory the case back is 1970 .1 ?

It has a newer 93150 bracelet with 580 end links , I would like to source a era correct 9315 they do crop up on vrf , would it be acceptable to fit a 1970 9315 bracelet

Finally end links is it ok to fit either 280s-380s my ref guide seams to be unspecific

Many many thx for all the advice