Stones

If you look closely at the photo of Stone's shop on Upper Street N.1 in 1978 at this link:'
https://www.flickr.com/photos/sludgeulper/3153756014/in/photostream/
...you will see that the shop sign has 'J & F' included in the flourish of the first 'S' of their full name of J & F Stone Lighting and Radio Ltd. (a very similar logo to the one on the photo of the Brixton branch on this page). They had branches in lots of places in London, including Croydon and Sutton in south London, as this advert in the 'Sutton & Epsom Advertiser' dated 3rd December 1959 shows:
“J & F STONE LIGHTING & RADIO LIMITED. SUTTON: 211 HIGH STREET. VIGilant 6349; CROYDON: 78a HIGH STREET, CROYDON and 177-179 NORTH END. CROydon 6789.”
They also acquired the Bookers Lighting & Radio group in 1954.
See their entry on BRSA at this link:
https://britishrecordshoparchive.org/shops/bookers/

I found this in the 'Evening News (London)' dated 6th December 1957:
“J. & F. STONE (LIGHTING & RADIO) LTD. - BECKENHAM, KENT: 278 High St.; BERMONDSEY, S.E.1: 3 Old Kent Rd. (BER 40658); BOW, E.3: 522 Roman Rd. (ADV 5401); BRIGHTON, SUSSEX: 210 Western Rd.; BRIXTON, S.W.9: 22 Atlantic Rd. and 411a Brixton Rd.; CAMBERWELL, S.E.5: 53 Camberwell Green; CAMDEN TOWN, N.W.1: 70 High St. (EUS 2014); CATFORD, S.E.6: 1 The Broadway (HIT 6415); CITY, E.C.2: 135 Moorgate (MON 5013); CITY, E.C.3: 65 Fenchurch St. (ROY 6361); CLAPHAM, S.W 11: 268 Lavender Hill (BAT 6746); CLAPHAM JUNCTION, S.W.11: 43 St. John's Rd.; CROYDON, SURREY: 78 High St. and 177 North End; DALSTON, E.8: 47 Kingsland High St.; DEPTFORD, S.E.8: 40 High St. (EDM 2932).”

With reference to Joe Meek working for Stone's on the Edgware Road, I found this slightly later advert in the 'West London Observer' dated 7th January 1955:
“TELEVISION and RADIO ENGINEERS Required for Retail Radio Shops in all parts of London and Provinces. Excellent salary and weekly commission. Holidays with pay. Applicants should able to drive and vehicles are supplied. These are permanent pensionable positions for experienced men. Telephone for interview: Staff Manager: J. & F. STONE LIGHTING & RADIO, Edgware Road, The Hyde, Hendon, N.W.1 (Corner of Colindale Ave.). Tel. COLindale ??”