Unfortunately I, too, had been a recipient of a failed AC system.
I did try it, but on new on a Dodge RAM 2001, when it was not even 4 years old.
I tried to keep things in compliance, but succumbed to the allure of snake-oil.
Turns out that single can of 134a with dye and sealant brought many years of un-bothered AC to that rotten truck.
I do NOT endorse any snake-oil remedy, just stating my findings..