No original dial from this period will be luminous any longer as the tritium has a half life of around 15 years I think.
Getting it reapplied is a big 'no-no' for collectors and will negatively affect the value. However, it sounds like resale value isn't a big influence here. I'd advise against it but it's your call.
Incidentally, a good way to tell if the lume is original is to light it with a camera flash. It will then glow for a minute or so, with the indicted fading evenly. Any dead spots suggest the markets have been touched up with paint but I don't think that's occured here.