Good news! It looks like I've located a shop called "Unlimited Fabrications" in Denton, NC that makes attachments and they told me they can fabricate the Yanmar YL-210 mount no problem. I spoke with the owner, Ronnie, who was very friendly and helpful. They quoted me $425 for compact tractor pallet forks, plus $75 for the Yanmar mount fabrication. Pretty darn great! Here's a link to the pallet forks I've ordered:
Compact Tractor Pallet Forks & Frame - Unlimited Fabrications
Can't wait to get these bad boys - unfortunately I have to wait about 2 or 3 weeks due to their backlog.