Hi Michael,
Wonderful examples of period bird's head pommels that do recall the "mystery dagger" as well as the much (
much 
) later Bucks... You know, I have to admit - I never have once stopped to consider the pommel of the Bucks which are indeed stylized bird's head pommels, as I have always fixated on the blade profile.
So much for my powers of observation, eh?
Regards,
Chris