Nicely done, great thread and enjoyed going through your journey with you
I'm doing a Mavic MTB build and can attest to how difficult it is to get a complete group set
The Groupset if fairly easy to obtain the most difficult parts to get are
Brake lever Hoods as most are missing of perished. (Modolo Speedy’s)
The Headset's are quite rare & can be expensive.
And the Bottom Bracket, most of the used ones I have, have buggered bearings
The bearings were I think especially made for Mavic & the original one are impossible to obtain.
There is some available that are very very close to the originals but need a conversion kit made up. I am seriously thinking about getting some kits made to use the newer bearings.
They are 2mm too thin so need a couple of spacers made & the axel will need a 1mm sleeve as the bearing center hole is 17mm hole & the axel is 16mm diameter. I’ve got a mate of mine that has an engineering workshop & he assures me that it will not be a problem to do.
SSC rims are available & turn up from time to time (mostly on s/hand wheels) so it’s just a case of cutting out the original hub & rebuilding with a Mavic one.
Hope that helps