All can see on the Barrel, BNP (Crown over)'.....BSA GUNS LTD ENGLAND CARTRIDGE .22LR. .610" 039 in a cross looks like swords. BNP stamped on all other parts. And it weighs a ton Parker Hale peep sight, front sight element tunnel. Two barrel mounts for a tube scope if one EVER needed to fit one. I may be wrong but would the manufacture be around the 60s? The serial number is only three figures UG - - -Do you know which model?
BSA Small-bore Rifles; Identification by Specification Table
Historic Arms Resource Centre facility for British and Commonwealth Enfield and other Miniature calibre training and small-bore TARGET RIFLES (BSA- Birmingham Small Arms Co.), conversion units and accessories with representation of other nations' training rifles, plus Postal League competitions...www.rifleman.org.uk
BC.