Your search query on "G&H Lobe Pumps & Roots Blowers" returned the following results:

C188273 G&H Products 622 Rotary Lobe Pump Head (1-7/8"ID, 3"OD Sanitary Flanges) (295785074403)

G&H GHPD-422 Rotary Lobe Pump SS FOR PARTS H9 (386280177868)