Yep I dug it today. There's one stone missing on the opposite side and it is bent a bit as well. I'm hoping I didn't hit it with my shovel. Grrr. lol. BTW I subbed to your YT silverfiend.
The 800 represents the percentage of silver based on 1000; or 80%.
There should be another single digit number present that represents the size.
Yours looks similar to this one with the turquoise cabochons:
Antique Silver & Turquoise Thimble * Circa 1900 | eBay
Don....