Were you also looking for a gem size? I know you mentioned the griffin above, but which griffin? I only have the male griffin. The only PYO I have are the griffin, kirin, and the small dragon…so I couldn’t help you there.
If you have a MM ruler you could use that and look at chatons listed on the sites above.
I was wondering about the PYO griffin, he has room for something in his tail 😀 Also was hoping we could figure out ALL of them and get a sticky going! 😀