Ca 2p3/2 binding energy values.
Ca 2p3/2-2p1/2 splitting is 3.55 eV (for CaCO3).
In survey spectra of samples where magnesium is also present there can be an overlap of the Ca 2p region with Mg KLL structure.  In these cases it is better to use the Ca 2s peak for quantification. 

Standards taken at Surface Science Western.
Ca 2p3/2: 347.3 eV
P 2p3/2: 133.2 eV
P 2s: 190.7 eV
O 1s: 531.1 eV

Ca 2p3/2: 346.5-347.0 eV
O 1s: 531.1 eV
C 1s (CO3): 289.2-289.4 eV

Ca 2p3/2: 348.3 eV
O 1s: 532.5 eV
S 2p3/2: 169.6 eV

Gypsum (CaSO4 . 2H2O)
Ca 2p3/2: 348.1-348-3 eV
O 1s (SO4): 532.1- 532.4 eV; O 1s (H2O) 533.4 - 533.5 eV
S 2p3/2: 169.3eV
Ca 2p spectrum of CaSO4.