Instead of PEX, I'd suggest and use a roll of 160 or 200 psi rated PE tubing with insert/barbed fittings using properly torqued double opposed (2 clamps each joint) marine grade SS hose clamps.
A few million wells use the same and have for decades. You'll have a higher flow rate due to PE's larger ID. PE is IPS (iron pipe size) as opposed to PEX which is CTS (copper tubing size). And PE will be less expensive.
Any plumbing, pump or well supply house has everything you need, including the torque wrench.
I would use SS or lead free brass fittings for either PEX or PE.