Whitby seems to have made a number of variations on the rudder stock. Michael Grosh has donated these drawings dated 22 July 1969, which he says is similar to what's on his 1967 rudder. This drawing is also available in TIFF format.
A serious magazine for serious sailors. This magazine deals extensively
with all sorts of navigation, from ded reckoning to radar and GPS. Also
significant coverage of other issues of offshore (or other challenging) sailing.