I agree with Andy. Even if you replace a part with one that is "original" to another unit, it's still not truely original. I suppose it depends how collectors feel about that and how it affects it the value of a vintage effect.
The funny thing about capacitors is that they have a shelf life (at least electrolytics do), and I don't know why you would want an old part like that which could potentially fail or be noisy. But there obviously is a market, else no one would be putting up auctions for these "original" parts...
(BTW - the capacitor I linked to sold at the asking price!! Gather all your NOS parts and start selling...
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