I wos wrong..
In the 1966/7 Ever Ready catalogue there are:
D size: U2, LPU2 (the designation SP2 had presumably not yet been used) and HP2 C size: U11, LPU11, HP11 AA size: HP7 and U12/D14. Note the dual designation. It's also interesting that the HP7 is listed twice, once in High Power Batteries and again in General Purpose. AAA size: U16, HP16