The Canon Canonet QL17 and QL19 rangefinder small body versions with 40mm lens - these are the ones with the 40mm f/1.7 or f/1.9 lens. There is the G-III version Paul mentioned, but also an earlier version not labeled "G-III" that still has the 40mm lens and small body. The earlier series of Canonets has a larger body and 45mm lens and take larger filters.
If you use a 48mm rubber hood then it may obscure a lot of the Canonet viewfinder, but it is possible to find a metal "vented" hood in 48mm that is much less obtrusive.