The illustrated PSE certificate calls this stamp as a simple R151, with shortened perforations at two areas.
So, somebody got a certificate for a stamp that catalogs twenty five cents.
But then there's some weird bar coded slip that is shown, that says that this stamp (or something else entirely) is actually R135a, a vermilion error of color.
Which is apparently why the seller is asking $350 plus $14.43 for shipping for this stamp?
Perhaps an interesting way to recoup your substantial loss after submitting a stamp for certification, when what you thought something was turned out to be something else altogether?