I'll admit I'm a complete noob here; I've never had any of my watches serviced, as most of them are quite cheap.
Does having a movement "serviced" mean complete disassembly of the watch and movement, cleaning the parts, oiling, and reassembly? If so, there's a very high chance for the watchmaker to damage the watch/dial/hands too, esp. with the rep hands being so fragile and the watchmaker may not have experience working on rep watches.
My other thought is, if a watchmaker is willing to service our rep with 7750 sec@6, it might be the best time to have the graphite applied? since the hardest part in this whole procedure doesn't lie in applying the graphite but in removing the dial and hands without damaging them.