Home Depot and Lowes (and I'm sure many other places) sell braided supply lines with 1/2" NPT ends. Buy a couple of those and add them at the pump. You could also use Tygon tubing and some barbed fittings but I trust the premade hoses more.
You might have to cut the ends off the PEX tubing at the pump and replace them but they sell the fittings for that too. Just check first so you'll know what all you need.
You might also want to mount the pump on some vibration damping material while you're at it.