The Richard Seaman Trophy is indeed a VSCC race. It was held at Silverstone between 1950 and 1954. In 1955 it moved to Oulton Park, becoming two separate events in 1963. In recent years the Seaman Trophies have been run at both Donington Park and Snetterton.
There is also a Richard Seaman Trophy awarded by the BRDC as part of their Gold Star awards; it now goes to the driver who scored most Gold Star points outside Formula 1 - in 2016, for example, it was won by Jann Mardenborough.
https://www.gtplanet.net/jann-marden...seaman-trophy/
Lando Norris is the current holder.
Back in 1950 it was won by Stirling Moss, for being the 'British driver gaining the greatest number of points in foreign races.'
