if your doing it for sentimental value then id call around and find a anodizer and have it done proper, keep in mind its gonna cost ya some money.
if your just looking to clean up a old gun then you could go a couple routes like mentioned above.
the cheapest and fastest way would of course be to get some Kryon and paint it any color or pattern you want.
the step up and what i would probably do in your position would be to either send it to Arma-coat in Edmonton or buy one of their kits.
they also do hot oxide as well which is a option as well.
there are a couple guys around that do Cerakote, never had it done myself but i think its $$ to have someone do it for ya, you can like the Arma-coat buy kits to do it yourself.