Hi Flip
You are right , it s a very strange link on your !
I have a poor Photo in my library !!
If this can help you , I m happy ; but I can t make better !
I have check my Watling Four Column Mint Vendor ( the same of your ) but not the same linkage ( A blue seal link !! ) !
And If some one have a Lock for the front casting Or some Photos for try to make one , or any info , please let me know !!
Stephane