Watch List notes:

(g) PF66 ULTRA CAMEO | Elizabeth II (1952-), Proof Sovereign, 1989, '500th Anniversary of the Sovereign', by Sindall, Queen seated in King Edward's chair, rev. Tudor Rose, edge milled, 12h (Marsh 313H; Spink SC3), brilliant uncirculated, in NGC holder, graded PF66 ULTRA CAMEO (Cert. #5878626-009) [Tied 1 of 10 / 325 Finer].
https://www.ngccoin.com/certlookup/5878626-009/66/
Estimate: £600 - £800