About $75 US for everything as of June, 2022.
New seal kit from Amazon for $40
Fork Oil for $14 (10W)
O-rings for caps (400pc set) $8. Only used 2.
Fence clamps (2 pack from Amazon) $12. Only used 1.
Radiator hose clamp $2 (I had a spare)
Reused the drain bolt washers (BMW shop did not have them in stock and would take over a week to get). No leaks so far.

Links:


F650CS Wiki:
http://f650cs.wikidot.com/forksealchange

Fork seals:
All Balls Racing 56-161 Fork and Dust Seal Kit https://a.co/d/iGiAK5o

Fence clamp:
Milescraft 4009 FenceClamps- Universal,Silver https://a.co/d/441EJWa

Fork oil: (I got mine from cycle gear locally)
Maxima 55901 10WT Standard Hydraulic Fork Oil - 1 Liter Bottle , BLACK https://a.co/d/fytKi6y