Here are some images of the 800 tray and the marks. One of the marks appears to show "0.800", and another one says "M.R". I could not make out what it said in the other cartouche. This to me doesn't appear to be usual silver marks, but more like an artist's signature. Has anyone seen this mark/signature before? Thank you in advance!
![Image](https://i.ibb.co/BNxhzcc/s-l1600.jpg)
![Image](https://i.ibb.co/4KZK17x/s-l1601.jpg)
![Image](https://i.ibb.co/4FK7bVz/s-l1602.jpg)