Why can't reloads legally be sold? Far as I know, there are no laws prohibiting the sale of reloads despite the obvious fact surrounding the questionable charges contained therein, it is caveat emptor.
IF, what I expect is being said: The ammunition can't be sold because he doesn't have a firearm license, then he likewise can't legally own them...
However, the executor of the estate is exempt even in the case of prohibited firearms, and lawfully given a "reasonable" time to "dispose" of these items whether by sale to licensed buyer, destruction or deactivation.
https://nfa.ca/resource-items/information-executors-regarding-firearms
OP, while the executor of the estate can own and sell these things legally, selling reloads as already posted is difficult unless the buyer is interested in the components. Sorry for your loss and good luck (executor) selling, but these are not uncommon calibers: While the 44mag might be worth someones time to (if they don't want to take the chance shooting) disassemble, (and to a lesser extent the 357mag and 45acp) and reload to their own specs, 9mm is not so expensive that doing so is likely not worth the time.