Hi Dave.
Having done a full resto last year on my ‘750 K2 I was too faced with this problem. I’m no longer in the UK (ie Oz), but quickly learned that commercially / small plating amounts was a problem - so much so that I was essentially forced into doing my own Zinc platings. Did I enjoy it - nope. An awful lot of prep and fussing. Cheap? Erm, reasonable. Results? - fine, but only with great prep and a quality kit.
So - it all got done, to an acceptable quality, and included such refinements as gold passivating.
Not advocating home plating; but saying it’s certainly doable if you’ve the inclination.