How to Fix Sticky Vinyl Imitation Leather

[RJBowman]

Yes, this is a little off topic, but might be of value to someone.

So I have a doll-size imitation-leather aviator's helmet and jacket. The toy that is goes to is actually valuable. The problem is that the imitation leather, which appears to be PVC bonded to cloth backing, is sticky. This is not caused by dirt, but the the vinyl breaking down after a quarter century of exposure to air or what have you.

I have found web sites recommending that bottled vinyl restorer or silicone sealer be used on this material. Does anyone here have any experience with these bottled preparations? If so, can you recommend a product, and advise me in its use?

Thank you for any suggestions.