Mounting Graham B44 arm on SME 20/2

Let me add some more context.

I was tracking the box along the way and at some point the status shown changed to "Delivery Exception, We will notify you when the package starts moving again". I waited 2-3 days and the status was not changing. Then I called FEDEX. I was told "your package cannot be delivered because when we scanned it there are no contents". Of course, you can imagine my reaction. Apparently, FEDEX scans the packages at each depot along the way, and they refused to deliver an empty box, out of embarrassment?. It does sound fishy, as they realized that the package had been scanned previously and it was not flagged as empty. The only logical explanation is theft by FEDEX employees. A claim has been filed but what good is that at this point.

Is it possible the seller forgot to put it in the box? Seems an odd thing to steal.

When I was selling LPs on ebay, a few times, I turned the box over, taped the label on, put it in the stack, then, later, checking the stack, oh, this one's empty, not sealed on the back side.

Bizarre. I suggest complaining all the way up the line in the Fedex system.  What right have they got to arbitrarily decide not to deliver even an empty box?  If you had the empty box, you might at least use that to discuss with the sender. But as you suggest, it may be that the package was stolen somewhere in PA, and they don’t want to acknowledge it. People like to disparage the USPS but I use their priority mail for packages all the time and have never had a problem. Whereas I am always holding my breath when it comes to Fedex, "Castaway" notwithstanding. I recently bought an expensive linestage, and it arrived via Fedex with ALL of the large output coupling capacitors having been shaken loose inside the chassis. Two out of 4 of them were broken off at both ends, so they were bouncing around inside. And other damage was done as well, even in the correct ARC factory shipping box. Fortunately for me, the seller, a dealer in Minnesota, was an upright guy who took all responsibility, because I know Fedex would never have done so.

Did the seller forgot to put it in the box? Did the the seller not put it in the box for whatever reason?

Obvious questions but very unlikely. I have been in constant contact with the seller who is willing to take back the arm for a full refund of the sale, if within a reasonable time another adapter is not found. There does not seem to be a motivation for the seller to not ship it. Besides, he is a younger guy, not like some old folk forgetting where he left his keys!

can you post a photo of the part you need?

is this bottom plate what you need?

can this work? it's the right diameter hole ....

https://www.ebay.com/itm/135145360450?mkrid=711-53200-19255-0&campid=5338722076&customid=&toolid=10050

maybe these guys can make you a part

https://www.artisanfidelity.com/tonearms/graham-phantom-b44-supreme

see the plate under this arm