Dear friends: Next there are some interesting caps information I found out in the internet that for some experts like you is nothing " new " but for people like me could be of interest ( yes, I know the way of thinking of audiophiles: " I like what I'm listening no matters what. " ) :
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The original paper capacitors in your radio will likely be in a brown paper tubular case (sometimes coated with wax).
Old paper/wax capacitors are one of the most unreliable parts in an old radio. Don't let "molded" paper capacitors fool you. They are just paper capacitors in plastic cases and are just as unreliable as the ones coated in wax . """
Paper-wax? is something used 70 long years ago. Go figure ! ! 70 years and we are really satisfied with the boutique caps that use those same characteristics and guess what: today we have ( for the audiophiles that touted almost everything. ) boutique fuses with bee-wax and I'm sure that the ones that bought or buy it will post somewhere that are something outstanding.
https://sound-au.com/articles/capacitors.htm#s80
http://zerocapcable.com/?page_id=224
Regards and enjoy the MUSIC NOT DISTORTIONS,
R.