https://greekreporter.com/2021/09/21/ancient-corinthian-helmet-found-in-southwest-russia/
In the Taman peninsula. Technically IIRC Bosporos wasn't a "kingdom" as early as the date of this find, but close enough.
A nice find - though this is a recycled story.
https://archaeologynewsnetwork.blogspot.com/2018/05/corinthian-helmet-found-at-excavations.html
Google also lists 2018 as the date of the greekreporter story. Greekreporter seems to make a habit of doing this.
They do, don't they? I shall try to remember to check in the future!
Given the classical Greeks were not usually into grave goods very much, does perhaps place a question mark on the assumed ethnicity of the chap in the grave.