You might want to think 2 pumps in parallel
instead of 1 bigger pump.. your looking for
flow not pressure.. I have been running 2
pumps on the race car since day 1.. they dont
need to be pricey.. the one thing about cheaper
pumps is they tent to be a little noisier.. but
if you isolate them they arent bad
EDIT
Also if one dies you can still make it home
or back to the pits