John I think your best bet for a donor deck is an aluminum deck off of a model like the 8255, or a similar late model D-400 shaft drive. That's what I did for the D-400 in my avatar. They are a bit heavier than Magnesium, but It will match up with your commercial model much better since the original commercials were aluminum anyway. Everything about the aluminum is better in my opinion. Those pop up on ebay quite often. You will have a couple of holes to fill, but that's no problem.
Been looking at that for a week or so now, price seems fairly reasonable for the whole fleet I hope somebody on here scoops them upCollection of antique mowers:
I think the green deck 14SB wheels are the ones that fit Lawnboys and are discontinued. The ones you linked to fit the silver deck 14SB & similar plus the newer green decks JX75, JS65, etc. They are also made by Oregon.Looks like John Deere is now making wheels again for those the 14SB, and all the others from that era. Great news! If I’m not mistaken those wheels will work on the Lawnboys from that era as well. So many of those early 90’s models were discarded due to the fact that drive wheels were no longer available, now it looks like we can save those models from being tossed. Here is an eBay link below. I hope these are new, and not just leftover NOS. Judging from the fact that 34 were sold already I would think they are in production once again.