Electrical questions! first big build

[formality]

Hi everyone i am about to do my first big build in my jeep, im going to be running 4 re sxx 18 d2s wired to one ohm running off of 2 sundown audio 2500.1s, now my questions are to start what brand of alternator should i be looking at? would 270 amps be alright for this set up? and as far as batterys what am i going to need, as of right now i have a duracel gold top up front should i replace that or well that be ok? i am on a semi budget but im already balls deep the woofers are in my appartment so help me out guys!