I'm afraid the Personna Pathology blades are about it, they are carbon steel so at least you can try to improve the edge. I cork mine before the first use, and then strop after each use with an Ingersoll Dollar Stropping outfit (check ebay, they are blade specific and most of the ones I see for sale are the Durham-oriented ones). I manage to get about 6 shaves out of blade using the razor like an SE, only one edge per shave. I flip the blades around between shaves so I'm using an edge every other shave.
If you can't find an Ingersoll stropper, get a complete Durham Duplex outfit that still has the stropping attachment and use that to strop the blade the traditional way. There are plenty of them on the bay and most go for little $$.
What a beauty ! Your handle is absolutely genuine, note also the cap that doesn't have the little spurs in the corners. This is uncommon, but also genuine. The Kirby references indicates your razor is a number #5, sometimes called "#5 publicitaire", this name variant can mean two things, not sure which is correct : either the baseplate of this model had bigger writing so the brand stands out, or the case was in cardboard with the name standing out.
