Replacement fresh water tank question

I welded up my 120 gallon freshwater tank, if it is new enough you might get a replacement BuT mine was 15 years old. I took an old soldering iron 150 wall and silver soldered a stainless pad to the copper of the soldering iron and purchased some rods of the same material and welded it up started by making mistakes and making it larger then it was the got the hang of it and welded a seem on the bottom about 18 in long. and it has been in service for over 2 years and took a 4000 miles trip this year did not leak a drop. May be worth a try. I did have to remove it from the trailer and also added a some support to the tank. Good luck there was not anybody in the Los Angeles area that does this any more.