Re-chroming original parts helps with keeping the original fit and appearance. A lot of repro parts like vent window frames will have issues that make them difficult to fit right.
General rule of thumb with chroming, though, is if the part has too much detail, it will be expensive to do and probably not turn out as nice as you would like. Convertible visor pivot brackets are one of those items, very difficult to do these correctly, finding NOS would be ideal in that situation.
I use a shop in Erie, PA called Qual-Krom. Bob, the owner, has been doing restoration work for many years and his chrome/stainless work is top notch. Just be sure to tell him to retain original detail in the parts and be sure not to sand edges that could change the appearance.