Hi Rusty,
Can you post a picture? Without context, that sounds pretty high to me for a plain Jane concentric circle (or oval) handstamp, even with the Pacific Mail connection.
We've had plenty of discussions about the stright-line PMSS cancels, whose premiums are considerable, frequently turning 50-cent stamps into $100-300 stamps. The other PMSS cancel that is very tough and commands a premium is the rounded box cancel shown below. This one is actually more scarce than the majority of the stright line handstamps. I put it in the $150 range.

The oval handstamps command a bit of a premium, but nowhere that of the ones discussed above. For example, this stamp catalogs $125, and I put the retail value of this example at $175. So yes, a premium, but not the magnitude of the others.
