Personnal opinion.

Clean it up the best you can.

Enjoy shooting it.

You said the only advantage was being cheap.

If you go overboard on it. IE changing caliber, shortening the barrel, refinishing it (if it isn't a hack job).
You most certainly will:

1- loose your advantage.
2- add nothing to the valour.
3 - maybe even detract some.

Just my 2 cents.

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