All of the retailers below (in no particular order) were, at one time or another, agents for T Withers (Electronics).
NW Electrics was located at 52 Great Ancoats Street, Manchester (more or less across from what were the Daily Express offices). NW was run by Fred Nicholls G3MAX with, I believe, G3SMI. NW also used to sell ex W.D. equipment like the PCR3 and R220 receivers plus 'bits' for AR88s & HROs, crystals, keys, components and the well known (at the time) G3FIF mobile whips. At that time (late 1960s/early 70s) there were quite a lot of radio (particularly ex WD equipment) emporia in that general area of Manchester including New Cross Radio, Globe Radio and many others whose names I cannot remember.
GW Smith and Co (Radio) Ltd
GW Smith and Co (Radio) Ltd was located at 3-34 Lisle Street, London W.C.2. They were also agents for Codar equipment. Other radios that were available from them in the 1960's were from Lafayette, Hallicrafters and the ubiquitous RCA AR88D and LF. The company also sold a range of other electronic equipment such as panel meters, silicon rectifiers, relays, field strength meters etc.
Electroniques (STC) Ltd
Electroniques (STC) Ltd were located in Harlow, Essex and were known primarily for Qoilpax receiver front end units. They also produced (in the late 60s) a Hobbies Manual.
Stephens-James Ltd was located at 70 Priory Road, Anfield, Liverpool (very close to Liverpool F.C.) and was run by G3LRB Jack Stephens and Harry James G3MCN. (The firm moved out of Liverpool in 1975 and went to 47 Warrington Road, Leigh). They also sold radios from Eddystone, Codar, National, and RCA AR88s, not forgetting to mention 'Joystick' antennas.
Chas H Young Ltd
Chas H Young Ltd was located at 170-172 Corporation Street, Birmingham. They were also agents for Eddystone, National, KW, Mosley Aerials. They also sold a range of cables, ropes, guys, spreaders, wavemeters, and other electronic equipment.