Another option is to take the output of the one amp regulator and feed it into the base of a much larger NPN transistor. Tie the collector of that transistor to the unregulated voltage and the emitter will supply much higher current at regulated voltage. The transistor will cause a 0.6 volt drop in the output voltage, which can be compensated by adding a diode in line with the grounded terminal of the voltage regulator.Sorry, I didn't read through all the posts before posting.
There are to-3 can voltage regulators too that can run 3 amps and not have to use three 1 amp regulators.