Here's my baby:
After searching EBAY quite casually for a couple years, I finally came across the socketed board you see in the photo. The key is to find an SE/30 seller who will shot a photo of the inside. That's how I found this board. And to save money on the shipping I asked for the logic board only. The seller was happy to accommodate that as he could sell the rest of the machine for parts.
Now if you are talking about "socketed upgrades" for the SE/30 being ultra-rare, then yes, I've never seen one sold on EBAY in the last 5 years of looking. They must be out there though, most likely hidden inside an SE/30 which the EBAY seller is unwilling to open. Then the person buying it either doesn't know its there or they keep it secret. But I cannot believe that only a couple hundred of those socketed upgrades were ever made, which would explain why we never see them on EBAY. Certainly, they must be out there, somewhere!