Saving Old Seagulls

I am currently rebuilding a recently acquired 1977 40+ unused for 5+ years
It has a very nice S/S drive tube, presumabley not O.E. Where might this have beem made / are they commonplace?

Most of it's nuts and bolts are S/S too. I am also replacing the exhaust tube for S/S as per Oysters Little Forty.
Should make a nice little motor if I can find a decent tank for it.

picture please .

Here you go .... Not sure if it shows the material very well. It has a slightly satin 'turned' finish and no rust !

If you search on this topic I posted a Seagull technical report on this subject some time ago.

Looks like a home made top collar welded to the original flange. Neat job though.