high current charge pump

You simply modify the circuit with current boost transistors using the existing circuit to drive them along with larger caps after the boost circuit.. Basically, this involves a simply totem pole unity gain stage being driven via the existing circuit. the Feed back for regulation starts from the output of this stage back to the driving device.

Depending on what kind of configuration you start with will determine if you need a single end out boost or complementary pairs.

Above is a good example of a complementary set that can handle up to 5 AMPS.

You must understand how your existing charge pump regulator works and assist it's output with current boosting transistors before it's feed back to it's sense input for regulation. All you need is to enlarge the cap sizes which will be handled by the boost transistors etc.

I remember making a cheap (-) doubled voltage source via a 555 timer that employed current boost transistors for a larger charge pump that other wise could not be handled via the timer alone..

This was years!!!!!!!!!!!! ago.

Most of these 'charge pump' devices are switch/capacitor devices, and the power efficiency is poor (under 50% of input power is delivered to the load).

If your output is to be 2A at +/- 24VDC, that's 100W; use a switchmode DC/DC converter, with transformer, for that kind of application.