Anyone selling the immediate precursor to amphetamine online is probably a DEA honeypot.
You could conceivably synth it yourself (assuming you had the right training and equipment) via a Henry reaction, except anyone selling the necessary reagents is going to eventually get you in trouble with the DEA, either because both of the precursors for P2NP are considered List I chemicals and sales are tightly regulated, or because they're just another DEA honeypot. Or you could get lucky and it's just a scammer.
But seriously, sourcing drugs and/or precursors is prohibited here.