I would be very careful with electrolysis:
1. it is a microscopically thin film on the surface and very easily worn off
2. silver leafing would put a layer on closer to what was originally on there
3. after the leafing, then putting on a protective layer of something would be more protective over all than electrolysis
4. because it does not last, jewelers do not do electrolysis anymore
These are some of my thoughts - good luck.