Thank you everyone for your responses! The tray, 2 pots and sugar/creamer were all a gift about 30 years ago. I do not know the maker but will look next time I'm there in a few weeks. I do not feel the plating on the rim alone has all been rubbed off at it would be uneven - some plate left on in certain areas. It's not flat, a rolled edge; which is why I felt it may be of a different metal under the plate (so it could be sodered onto the tray). The leg base for one of the coffee pots is affected the same way. Mother-in-law has been very gentle and good to this set all these years. I will look for International Silver polish, and try a brass and/or copper cleaner on a section underside. I may try contacting the company who plated it, if they are still in business. This is not a cheap quality set and I would hate to do it more harm! Again, thank you!!

I also decorate with mine, keeping it all together in the kitchen~a large rectangular tray is over my cooktop, on the right side is another tray(round)leaning against the backsplash. A SS water pitcher holds old SS utincils. In front of that is a small lamp made out of an old SS sugar bowl. I also made a paper towel holder out of a candleabra which sits next to the pitcher. On the other side of the cooktop is a long narrow SS tray holding a crystal sugar bowl and creamer, crystal salt/pepper shakers, and toothpick holder. For years I kept my 'stuff' in a box, but 4 years ago when I mover into the new house, decided I didn't want to be a collector of stuff, but a 'user' of things I love. ;o)

Well, I heard back from the lady I thought might be able to help you find the perfect tray, but I think it might be a bust. She located three trays she said are very close to your inspiration pic, one 24 inches and the other 25 inches and around $650-750. Bad part, they are new. :( The other she found is 31 inches and circa 1850, sounds perfect, right? Then I heard the price, $6500. Had to pick my jaw up of the floor and think that the 1st Dibs tray is looking especially good now, even though I already thought it was a cool piece. By the way, did you see the marble tray in the WSJ this weekend? Probably not what you want since you have an inspiration room with a great silver tray, but what a great piece. Anyway, good luck with your continued search. Hope you have success this week in NYC.

Here is another close-up of the stamp with what appear to be two sequences of letters: four in the top sequence and three in the bottom. Looks to me like the first two letters in the top sequence are SP, which I might guess means silver plate? For the bottom sequence, I have only a guess. But it appears to be "ON C". Would that mean "on copper"? Unsure about the last two letters of the top sequence and completely uncertain about the bottom.