Timely topic for me. I have an old 12 speed that I converted to a single speed that I want to convert to a 3 speed. It has 27 1/4 wheels with chrome rims. I like the rims because they are so shiny. Can one of these custom wheel building shops use my existing rims to add a SA 3 speed or would I be better off getting a new wheelset (700c) that already has a SA 3 speed like the one shown on the Velo Orange site?

I'm not asking for opinions on 27 1/4 vs 700c, instead I'm curious to know whether using my existing rims is a good/bad idea when it comes to adding a SA 3 speed. Thanks