Scarlet,
You may find Ian's wisdom a comfort when you discover nobody stocks it anyway. (Actually if you do find some please let me know 'cos I need a bit of vulcanised red fibre board for something else). I did in the past substitute copper or brass sheet without detriment.
btw the old packing I have was more like 1/16" than 3/16", though heaven knows what's 'correct'.
You may find Ian's wisdom a comfort when you discover nobody stocks it anyway. (Actually if you do find some please let me know 'cos I need a bit of vulcanised red fibre board for something else). I did in the past substitute copper or brass sheet without detriment.
btw the old packing I have was more like 1/16" than 3/16", though heaven knows what's 'correct'.