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I've never tried cleaning a coin myself but I don't think I'd start with that one.
This is, to my mind, not only a special case but a numismatic emergency. PVC contamination is
active. Without intervention, it *will* wreck the coin beyond any real numismatic value. You'll normally hear me being much more conservative regarding acetone - I would
never recommend acetone for a coin of this appearance absent the PVC.
Arcticsparky, the major Third-Party Graders (TPGs) will only offer their "normal" slabs for coins judged to be in completely original condition. Cleaning, accidental marks/scratches, environmental damage, all these and others will lead to what's called a "details" grade. The slab will be the same, but a notation will be made on it that the surfaces are not original. This, of course, leads to a substantial reduction in retail value.
Given the likely PVC contamination, your coin will likely get a Details grade anyways. No
TPG will slab a coin at all which has an active PVC problem; they know it will destroy the coin if left unchecked. Only NGC's sister company, NCS, will professionally remove the PVC for you and then pass it on to NGC for encapsulation.
For the record, PVC is a plastic additive (polyvinyl chloride) used as a softening agent to make the plastic less brittle. Smell a new shower curtain - that's PVC. Its' outgassing interacts with silver, literally eating it away. And unfortunately, it used to be very commonly used in coin flips and containers. You're paying the price for that previous use.