Hi Marvin,
My very personal point of view...
Is the dagger for you? or you are planning to sell it?
IMHO if it is for you... do what you feel better... whatever it gives you more pleasure when watching the piece.
If you plan to sell it... I think you should keep it as it is. A 80 years old piece must look at least old. A repaint would make it look as new...
If you plan to keep it, the market value doesn't matter so feel free, but if you plan to sell it... guys like me woult preffer to touch history better than touch mint paint...
Sorry for my english.
Kind regards,
Marc
