Great britain - Enfield
British license receiver and barrel markings.
"Crown over RSAF " indicates it's made by Royal Small Arms Factory Enfield, Great Britain.
AFAIK the G3's made by Enfield were for the most part assembled by H&K made german parts.
I have seen an Enfield made G3 with Ulm proof house (stag horn) stamps which is quite odd.
Enfield G3's are normally stamped G3 EN and serial number or
G3A3/G3A4 and serial number in the upper part of the left magwell and EN and datecode below the serial.

Detail pic of the bolt head marked RSAF.