I have a very nice stainless steel heavy bottom pot, 18/20 thickness. Unfortunatly, it only holds 1 1/2 gal max. I did extensive research for comparable pots online, the cost is insane (average of 100.00$ for 16qt).
So, i went the other way. i already had a 30qt aluminum that I use for my waterbath canning, i found an inexpensive 16qt online, and i double boil. it really is not as hard as it sounds. i was overwhelmed my first time, but it gets easier.
one note....my 16qt only holds 2 1/2 gal because the rivets on the handles leak....i DO NOT recommend the Imusa brand ss stockpots!
so good luck, and i hope this helps!