Those fat ones used on pommy bikes back in the day were known as "Beston" grips. I have a set on my Jota, and I find them more comfortable than the usual thin type found on Italian bikes.
Re your comment about diameter, I assume you're talking about the outside diameter (99% of grips have the same ID). I've not seen the Nava ones in the flesh (or plastic), but they appear to have a similar profile to the Beston type in photos.
When I bought my Kawasaki 1300, it had massively thick foam grips that were about 2" in diameter. They had chrome end plates embossed with "Harley Davidson" . They looked stupid and felt wrong. I can understand why you might want thick vibration absorbing grips on a Harley, but a 6-cylinder Kawasaki 1300 is one of the smoothest running bikes ever built. Needless to say, those idiotic grips got replaced with a sensible type within a couple of days.