Post Office GPO Round, Eagle & Dolphin Seal, 1691-1708

Older Royal Mail GPO Seal, Image & Found by Adri@n POST with Crown Seal, Image & Found by Adri@n.

I believe this is an early version of the G.P.O. round bag seal.
See similar:- UKDFD Ref. No. - 15078

Another seal has come to light indicating that the "Russian Eagle" pattern is fact a complex coat of arms showing a dragon and dolphin. See other GPO round seals.

Updated discription after seeing PAS record WILT-AFD0C4 identified by Mr David Algar:-
"A Post-Medieval Post Office lead bag seal from the reign of William III (1689-1702) and Anne (1702-14) of the House of Stuart. It measures c.20mm in diameter and c.4mm in thickness, weighing 10.85g. It has slight wear and a perforation from one edge to the other where it has been cramped onto a cord.
Obverse: Crown above G·POS[T] (General Post) Reverse: Two oval shields, on the left, an eagle displayed, head left and on the right, a dolphin embowed left with two saltires in chief. This seal would have been used to secure the contents of mail bags or sacks. Date: 1690-1708 The seal bears in the oval shields the crest or arms of the senior and junior Postmaster General who held office from 1690-1708: Sir Robert Cotton [The Royal Mail Archive gives his date as Postmaster General as 1691-1708], an eagle displayed, and his deputy Thomas Frankland, a dolphin embowed below two saltires in chief."

Photo info