I would avoid powder coating - it can become brittle with age (UV light?) and then crack leading to moisture becoming trapped against the spokes. When we bought our last Morgan in 2003, Ben Duncan had just had the wheels re-finished by stove enameling (I think) which had not deteriorated by much by the time we sold the car in December 2013 (apart from the odd chip). I suggest you speak to a couple of dealers (Mike Duncan would be my choice) and ask them to recommend someone.
