I thought Murphy was a variety of potato but looking it up apparently it's just a slang term for any spud, I guess that's where the brand name came from. I vaguely remember Murphy's and Tudor but a definite regional one was Benson's from Blackburn - obviously available in Thwaites pubs in pre-T wa t s days. What ever happened to Golden Wonder?
My first encounter with pork scratchings was "Ernie Rounds" as sold in Bristol pubs in the 70s, - teeth breaking and complete with bristles - as disgusting then as they are now . The Village in Salisbury used to serve prawn crackers doused in chilli powder of a Sunday lunchtime - excellent with a pint of Landlord.