Parker Hale peep sight for Rem Lee BSA Supersport 5 Martini

Peep sight stamped 18DE by Parker Hale for the Remington Lee rifle as well as the BSA Supersport 5 and BSA Martini. Must be a later sight by PH because it's made of aluminum and not steel. Does not have a screw in aperture with it or mounting screws. 

$10 shipping.