Thank you Greg, I am not ready to call this a G&H rifle but your share has lifted the corners of my mouth. There sure seems to be a number of points of evidence pointing in the G&H direction.

I did find some pictures of a G&H Farquharson in which the maker of the action also was unknown. It had a G&H serial number and address on the barrel but nothing on the action. So quite similar to this rifle. Wish I had its original barrel.