This picture appears to derive from Van Dyck's whole-length portrait of an unknown man c.1638 at Hagley. Other versions include a half-length formerly at Littlecote (sold Sotheby's, 21 November 1985, lot 813) and bust-length miniature sold Sotheby's, 13 July 1982, lot 100. It is possible that this was a Cartwright picture; it appears to agree with his taste and was first catalogued as being in the College in Sparks & Carver 1890, as were the other Cartwright pictures.
You are all set!
Your first Culture Weekly will arrive this week.