i found a company in alberta from an old postRBW1531-2.pdf
. new tank, same measurements and hole location as the old one (you specify where you want the holes).
it was $220 plus shipping.
i thought about fixing the old tank, but was worries since the tank is 30 years old and is inside the trailer and if it ever leak again it would cause more than $200 damage it was better to invest in a new one
i will let you know how it turns out, should be here in less than a week