RISC OSMap of G.W. SignalboxesRISC OS
http://www.svrsig.org/gwmap/GWMap.htm
Sxxxx numberSignal Box nameView on map squareOther information including SRS diagram number
  Basingstoke (G.W.) Map DK38
SU641527
SRS diagram B289
  Bramley Map DL40
SU655594
SRS diagram P194 (1924, 194)
  Mortimer Map DL42
SU672640
SRS diagram D225
  Sherfield Map DK39
SU658560
SRS diagram S138
  Stratfieldsaye Map DL41
SU656624
SRS diagram D225 (1940 also Stratfield 1917)
Prices are shown here.