Mostly for my own reference, these are the lead acid cells I'm looking into:
group 24, 80Ah, $72
group 27, 105Ah, $75
Ironically, the little 26R OE replacement costs even more than either of the deep cycle batteries above:
26R starting battery, $89
So, its actually cheaper to go with either of the batteries that'll allow me to do an alternator delete... Works for me.