Hope this comes out OK; it is the 1st time I have tried using this or any other bulletin board!
Following your lead, I looked at "gasket" in my OED and thought the following was interesting. The first quoted nautical use was given as being in 1622 "R Hawkins: Voy.S.Sea - His sayles repayred and sufficiently prevented with martnets blayles and caskettes". By 1630 J Taylor in his Navy Landships (whatever they were - any ideas??) is using the modern form, "Her gaskets, martlines, cables", and all subsequent references given use this modern form "gasket".
The first "plumbing" use of the word is given as 1829 in a text book on steam engines.
An adjacent entry for the word "Gaskin" shows two meanings, one of which is an item of clothing - breech or hose - or the hinder thigh of a horse, while the second is given as an alteration of gasket and is shown as being applied in the 19th century in place of gasket in both the nautical and plumbing fields.
Incidentally, I am fascinated as to why the spell checker does not recognise "nautical", the nearest it can suggest is Navajo. I would not have thought nautical was an unusual word!