Yes, follow the model and serial designation on the deck simply because there may have been variations that were made across the production time of the model line. Doing that should keep you on the right track with the mower you are working on.
A few words of caution. Different sites show things differently, and some may show that a part is available, when in fact it is not. You can also do searches by a specific part number, when you know it, and sites that happen to be in the Honda network will come up, but they don't actually carry or offer such parts. I've looked for mower parts and been directed to motorcycle dealers as a result, but when contacted, they don't deal in out door products. On the other hand, I did need a part for a lawn mower that supposedly was no longer available as an out door power product, but the same part was used on one of their motorcycles, and it was still available as a motorcycle part.
Confusing? Just know for sure what it is you're looking for and you'll be O.K. Without being repetitive, boats.net is the best online retailer I've dealt with so far as price and service go, and I've bought a lot of parts over the years. Plus it pays to have a real good relationship with a Honda Power Equipment dealer if you have one nearby. The knowledge they have in their product line can't be beat, and who knows, maybe they have a bone yard of mowers and parts you can pick through.