About zero.
The collector output impedance is high, so the voltage at the output is essentially Vcc - Ic * Rc. The Vcc isn't reduced at all, it has gain 1, so the part of the output due to variation in Vcc is a ratio of 1, or PSRR of fuck all dB.
Perhaps a better way to think of it is a shift in the ground reference for the signal. Suppose you follow an NPN common emitter stage with a PNP common emitter stage. The PNP's input is relative to its emitter, which is now near Vcc. The Vcc term in the NPN's output cancels out with this, and PSRR is quite good (roughly Rc/Rearly).
Early effect is the name given to collector output impedance (i.e., change in collector current for a change in voltage -- the incremental resistance). It depends on transistor type and bias current. Typical figure would be in the 100s kohms for a preamp circuit like this, so PSRR in the 20-40dB range would be expected.
Note this assumes signal frequencies. That is, where the base bias divider doesn't contribute because the coupling caps and source impedance dominate. Base bias being derived from Vcc (as in the traditional four resistor, one transistor, 2-3 capacitor, common emitter circuit) does have an effect at other conditions, of course.
You can always improve Early effect say by stacking transistors in cascode. In that case, the PSRR about doubles, again contingent on being able to ignore bias dividers of course.
Tim