No start issue - likely fuel pump

[further]

Howdy all, after changing manifolds/risers and full tune up, I fired up the boat in the driveway and had a no start condition. Motor cranked and sounded like it wanted to start but dies... went through all my work and found new #8 plug wire broken at the plug end, so replaced and it started up and ran great... I think that was a coincidence because tonight I took the boat to the marina and again had the same no start condition. Went through all the plug wires again and all are fine. Felt like it may have been starving for fuel so got a tester and got 10-12psi on the low side and only 10 on the high. Obviously this is no good since I believe the high side/rail is supposed to be 50-60... question is, is this pressure with the key on and motor not running ( obviously motor won’t run so...). Also recommendations for replacement fuel pump? OEM are pricey .. I’ll bite the bullet but are there others to consider?
Thanks in advance

 

[saaristo]

Could it be that the low side is clogged? Paint chips and/or ethanol gunk making the HP pump starving? I might be totally wrong...