I looked too for a reference on the HAI site and found none.
As an FYI though I updated my OPII to the newest with upgradable FW and it works great. I currently have 4 of the 5 serial ports populated.
It wasn't difficult to update. I'm still using the older legacy OPII in FL and it continues also to function great.
The MFG price, wholesale price, street price are all going to be different. How fair are you looking to be on your offer?
The boards are built well and built to last. Only a rep from MFG will be able to tell you for sure what it is though I am guessing....they can look up the serial number for you too.