ECM 37820-plm-315 alternatives

The Electronic Control Module of my car listed above (LX) is fried and un-repairable; confirmed by an ECM repair shop. I know that I must now either get the matching key and switch for the used replacement or get the new one reprogrammed.

The repair manual says the replacement must be the same part number, but
the original part number is 37820-PLM-315.
I see in several online new parts listings that the -315 is referred to as a "replacement" for the 37820-PLM-L01 and 37820-PLM-L02.

Question 1: Can I replace the *-315 with a *-L01 or *-L02 without ill effects?

Question 2: What is the opinion from a mechanic who has replaced a similar old ECM about the advantages of:
A) Replacing only the ECM (new or refurbished) and having it reprogrammed to match existing key, or,
B) Replacing the ECM with a guaranteed used or refurbished unit with matching key and ignition lock.

I need an authoritative answer from a Honda mechanic who has done it many times. Because the 100% correct information means money to me, I’d be willing to pay for wise, experienced advice, rather than a pretty-good educated guess (although I’m open to all informed opinions).