Im told these could be worth something as a lot. I dont know too much about trays, maybe the experts can advise. If you want to make a serious offer then email me. Bear in mind these will cost me $25 to ship the lot securely from the UK.

There are 8 trays altogether, being consecutive calendars from 1974 to 1981. Im told thats all were made. 1974 to 1977 are lighter glass than the other 4. An example of each is shown below.

They dont scan so well due to their shape, but you can see where the light caught the gold that the horseshoe logo and word and the lines round the outside edge seem to be like gold leaf on the surface.
These trays were apparently either used in the casino or given to VIP's, they were not giftshop items. Other than a couple of tiny nicks on edges on two they seem to be in very good condition with no faults on the printing.
Actual size of trays is about 5-1/2inch square.