I, too, question your "need" for a hardening fixer for film. I have never used one, and I process sheet film in batches by hand in trays and agitate by shuffling.
I would submit, however, that your F-24 fix (if it is indeed the Kodak formula) may be inadequate for more modern films and especially for Delta/T-Max films. An ammonium thiosulfate (e.g. "rapid") fix is best for modern film emulsions.
It doesn't seem all that hard to get a rapid fix to use for your film processing. Northern Utah isn't that isolated from the rest of the world
FWIW, I use Ilford Hypam or Rapid Fix. You can buy a separate hardener for the former if you find you really need it.
Or, you can just use one of the hardening formulas if you mix your own (F-6 is a nice odorless formula, there are others too).
Best,
Doremus