I finally poked around enough at Needlebar and found a photo of another Pfaff "H"! It can be a challenge to navigate that site, but is SO worth it, IMO!
The photo they already had is of a machine that is not quite in as good of shape as yours, and has this caption. Interestingly enough, the Model "K" is a vibrating shuttle machine....
"[h=3]Pfaff Model H[/h]
Courtesy of Rick
Serial #808962
Pfaff models were originally given letters for identification, but later switched to numbering (as did other manufacturers). By 1916 they were using up to model 102.
The Pfaff H is a Central Bobbin machine and it became known as Pfaff 31"
[h=3][/h]