I purchased this watch off the bay and I am wondering about the movement size? It is a Illinois Stanley in 17 jewel and was listed as size 8. Everything I reference says only 7 jewels were produced in size 8 I have attached a couple pictures. Can anyone tell me about this watch and confirm the size? And can you provide movement diameter and height dimensions?
Thank you for your help.

The movement

If I read the serial number right 4338851, that is listed as a 12 size grade 405 stem set 17J made in 1923

Tom

Thank you very much Tom