Is Suikoden under Abandonware though? If it is, and once it is, then I don't think there's a big difference between getting only the bits of the product you want how you want, and getting a complete physical copy with manual etc. which one might not be interested in. Yes, you're creating a new copy of part of the product, but again, if it's abandonware, even if it's not legal, I don't see a problem ethically or morally in doing so since it's of no interest to the original makers.
If anything, I think buying a used copy would be morally worse since the person selling it to you would be the one getting paid for it and making money off an abandonware product, and probably at a higher price than the maker might have originally sold it due to the product's rarity.