Honestly, I think Warmoth might be your best bet. The one problem with their MIM necks (which fit Squier 5’s) is the in-line headstock shape. You will need to get a new set of tuning machines.
I have TWO Warmoth necks for my two Squier bodies. One fretted, one Fretless.
Both are Roasted Maple, fretted has roasted maple fretboard, Fretless is ebony.
A Roasted maple/Roasted maple with standard Dot inlays is the cheapest way to go. No finish required (standard steel reinforcement rods). The fretted neck was about $330 shipped.
I absolutely love how the neck feels - best neck I ever played, and it looks amazing
Outside of that, you can perhaps keep an eye out on Stratosphere for either a Squier or MIM Fender neck. They actually have ONE neck for a Fender Player Plus - nice neck. I’d probably get this one if I were you. The VM tuning machines should be a direct swap.
Not exactly “cheaper” than Warmoth, but you can get it a lot faster…
Fender Player Plus Jazz J V 5 String BASS NECK Bass Guitar Pau Ferro | eBay
A Squier neck would probably be $150 cheaper. I bought a VM neck from them (with tuners) in 2016 from them for $160. But they don’t have any at the moment.