On your Flickr page you call them HPNP and that is what it shows on the photo you posted. You also said they have 2 cutting edges.I don't know what you're talking about when you say "Looks like the insert you bought is no longer part of the deal." Here is the link to one of the four shell mill kits I bought that for $100 includes the shell mill, a package of 10 inserts, and a CAT40 arbor that I sold on eBay.
The link you provided they are called HRNP and they have 4 cutting edges. I was/am confused because I was trying to find the HPNP's.