The part is nowhere near that critical. I personally refuse to pay more than $1 to make one. I've used foam off lawn mowers and other gas powered equipment, even foam filter for small room air conditioner. Hobby foam may not work-solvents in oil may melt it.Also two different types of foam, open cell and closed cell, it must be open to flow air. Way you tell is to suck through a piece of it, if you can easily then it's open cell, if it's closed you can't suck freely through it. I've even used 1/4' thick material, roll it up like a thick carpet and turn roll on end to insert, make it a bit big to stay in place, like I said not critical.
It IS the PCV filter, the air path starts there, goes into valve cover and through motor, then out front PCV baffle and to intake. Flow changes direction only at much higher engine speeds.
Left over foam then used for chainsaw (I got like 4) filters and the like, maybe another car. $5 worth will replace easily $25+ worth of the exact part but some just feel they gotta have that exact part.