Can anyone give me some info on this?

It's not my expertise, so I can't comment on authenticity, but it looks to be a counter commemorating the dominion of the sea from the time of King Charles I. See the following link for an example from the Royal Museums in Greenwich:

https://www.rmg.co.uk/collections/objects/rmgc-object-38869

Looks like there are two initials on the arm/sleeve of the bust of Charles, that are an N and b, standing for Nicholas Briot. The very little I read about him state that he would become chief engraver to the Royal Mint in 1633. I'm not sure what they mean by counter; my mind wanders to Jetons and wonders if a counter is similar to a Jeton. This is just a musing of mine, and if I'm way off base someone please guide us back to the right way.

There are various medals with similar design to this:

1) https://www.rmg.co.uk/collections/objects/rmgc-object-38868
2) https://en.numista.com/catalogue/exonumia156006.html
3) https://www.gutenberg.org/cache/epub/49274/pg49274-images.html#Charles_I

• no pictures in link 3 but the descriptions of items 69-71 are similar to the item in your hand

4) https://www.historicmedals.com/viewItem.php?no=226
5) https://www.cngcoins.com/Coin.aspx?CoinID=310786
6) https://www.metmuseum.org/art/collection/search/230953