A good start would be to look at the tube data for your line up. Assume the amp will spend some time at full tilt. Add at least 20% for safety and to avoid too much sag in the power supply.
I think your fine with the stuff you have. But for education sake you should look it up for yourself. Tube data is easy to find. Figure for the calss of operation and maximum output under those circumstances for every tube in the amp. the current draw under max and typical operation is listed in the tube data. Easy peezy.
In truth some amps use a smallish power supply and have a certain sound because of it. To duplicate the amp your cloning just figure that amps tube line up current max and see how it stacks up to the mA rating of it's power transformer. Then see if your stuff will give you close to the same ratio.
You can also check the current draw for all your heaters to determine if you need to go with a diode rectifier or if you have enough rating to use the 6x4.