Based on the knowledge sources provided, I don't have specific information about retrieving a JWK by kid using the Go SDK for Ory. The documents contain API reference information about the JWK endpoints, but they don't include Go SDK examples for this specific operation. What I can tell you is that Ory provides an endpoint to get a JSON Web Key by its set ID and key ID (kid):

GET /admin/keys/{set}/{kid}

This endpoint returns a singular JSON Web Key contained in a set, identified by the set and the specific key ID (kid) [Ory API Reference](https://www.ory.sh/docs/reference/api) [Hydra API Reference](https://www.ory.sh/docs/hydra/reference/api). For using the Go SDK, you would likely need to use a client method that corresponds to this endpoint, but the exact method name and parameters aren't specified in the provided knowledge sources. If you need the exact Go SDK implementation, I would recommend checking the official Ory Go SDK documentation or examples, which would provide the specific client methods for interacting with the JWK endpoints.