SR Mariner Knotmeter gasket

[Juanvaldez]

Hi
My new to me boat has an old knotmeter that still works. I pulled it out of the through hull and was surprised to see no gasket. The internets led me to SR instruments where I wanted to purchase some gaskets and a spare impeller. On checkout I was surprised to get a shipping quote of over 30$


Can anyone tell me if it is a common oring size that I can buy at a hardware or automotive store. I'll pay the 30$ if I have to but would rather not. I'm in Canada so expect that is the reason for the high shipping

The dummy plug looks like this

[Wotname]

Around here, every size of O'ring is usually available from bearing supply shops. Normally identified by the internal diameter and the cross section thickness both in imperial and metric sizes . Uncommon ones make take a few days to source from the warehouse.

I would expect Canada would be similar.

[Juanvaldez]

Not likely an issue if I know what to order. Does not seem to be a regular oring though

[Dalestr]

The SR mariner speed transducers are sealed by a square cut O-ring that fits into a recession in the through hull so it is likely specialized though in a pinch a circular section o-ring might be workable but the thru hull is somewhat fragile here. You also don’t want it popping out while managing a 2” whole in your boat.