Value of 3 gal double line Johnson/Evinrude pressue tank

Gents:

What would you put the as a value on a 3 gal double line Johnson/Evinrude pressue tank?

Came off a mid 50's Johnson.

A few datails:
1) just a little rust outside. Its been coated with some kind of off-white coating which has helped keep the rust at bay, but that will be stripped, sanded and repainted.
2) rust inside is minor
3) no hose
4) Cap is nice

I'm not going to take it apart and replace gaskets or anything.

Thanks!

Depending on the condition $25 Canadian to start
I have seen ads on Kijiji.ca where the sellers are asking over $100 Canadian but those were in like new condition