Founded in the late 1870s, the Stanley Company was based for many decades in New Bank, Halifax England. They appear to have survived as an independent concern until August, 1979 when Hydro-Matic (Machine Tools) Ltd. - aiming to expand their product range - bought the assets and goodwill and moved into the Stanley works. Hydro-Matic had been founded in 1974 to specialise in Scan-O-Matic continuous-path hydraulic tracer controls for machine tools and, once established in their new factory, developed a new range of lathes, the types HSP, HM, L and LHM.  In addition to their standard ranges, Hydro-matic also offered machines built to a customer's particular requirements while continuing the manufacture of hollow-spindle, large-bore "Oil Country" and sliding-bed lathes (both a long-standing Stanley speciality), T-bed and facing lathes and deep-hole  boring machines. Today Stanley are still trading, now part of the  Broadbent-Stanley Group and making a wide variety of large and interesting machine tools. They remain in the Halifax area, now in their Holmfield Works on Shay Lane.
The catalogue extras below show the range of Stanley lathes as produced from the late 1940s until the 1970s.
Serial numbers: unfortunately detailed information is lacking, though the following is known for both standard and sliding-bed models:
1940….. 541
1943….. 715
1946….. 945
1949….. 1067
1952….. 1198
1955….. 1805
1958….. 2134
1961….. 2426
1964….. 2654
1967….. 2841
1970….. 2978