24LC512 - 512K EPROM 8
Exactly, you need 7 and one 256, because the last bank is for ensembles and only needs 256kb but it's no problem to use a 512, it's just more expensive.
The Voltage Regulators depend on which SIDs you use.
Are you sure you need 2 7809? I'm too lazy to check this but I can't imagine that you need 2.