Well, I got the pipe and its stem is a cheap plastic thing that doesn't actually fit well enough to stay put.
It just pops right out of the stummel.
I had choices. I could send it back at my expense for a 'full refund', or take an adjustment.
I was really discouraged about the pipe and really wished I'd never ever bid on the thing.
After a few email exchanges, the seller agreed to raise his adjustment offer from $5.00 to $10.00 and I accepted that.
I took the broken stem I had from my Cobitt Shire and sanded IT down to fit into the stummel of my Peterson Barrel and I'm smoking it as I write this post.
I may never bother to get a better stem made. What I've got now seems to be secure and air tight. It works.