Yes, that is also how I get my film - I buy it from a photographer who no longer has the opportunity to work in analog.
Something else, I work with Retrodinal, a variation of Parodinal that I learned about from my first posts on this site : (there was a url link here which no longer exists)
I have developed most of my work in it and I'm stunned, I have tried Parodinal, but Retrodinal is slightly easier to prepare, since it uses metabisulfate, and though I have left some exposed to air in an open jar for about a week, as a test for it's longevity, despite a very small change in color, there was no other alteration of its properties. When I conducted the same test with my Parodinal, the result was a dark, coffee-like liquid, that had poorer developing abilities.