Ordering rolex parts at an AD

[GIS8]

I bought a 90's TT GMT II a while back: if I wanted to order a bezel insert at an AD how would that work?

If I want to order a root beer insert, and my watch has a black bezel would they still be able to do the order? Or would they ask me to show them a root beer gmt to be able to order the part?

Also whilst I know prices differ from place to place most of the time, if I wanted to order the gold gmt hand set how much would that run for typically? (as in having them replaced)


Thanks in advance!