Watch List notes:

BRITISH COINS, Oliver Cromwell (died 1658), Silver Halfcrown, 1658, laureate and draped bust left, rev crowned quartered shield of arms of the Protectorate, HIB title for Ireland, edge inscribed in raised letters (N 2746; ESC 447; S 3227A). One or two tiny hairlines in fields, very fine, reverse about extremely fine, toned.
from the David Sellwood collection

Estimate: £3500-4000