An 18th Century English flintlock pistol

An 18th Century English flintlock pistol, brass barrel 5.5 in., engraved 'HEYLEN LONDON', struck with two crossed sceptre marks as of Ordnance private proof and with 'IR' under a crown, lock signed 'HEYLEN', double bridle pan and swan-neck cock, full stock with ornate white metal furniture including trophy of arms side plate, horn tipped ramrod.