The Mamiya clamp-on hoods are very sensitive to the diameter of any filters you may use, so while they are nice items, there are drawbacks. Over the years I have raided camera shop bits boxes and the odd camera shows for orphaned hoods of the right thread and length from various manufacturers, but generic 'standard' rubber hoods will work for the 80 and 105. You might want to standardize on 49mm screw-ins and use a stepping ring for the 46mm lenses. If you are using an older lens with a 40.5 thread it might take two steps.
Obviously it is good to get a hood that is optimum for the focal length (just out of view at infinity), but this may not be possible in practice.
The old double box hoods were fun to look at - a total pain to carry around but they did shield both taking and viewing lenses. But a rigid lens hood almost as large as the camera body is a bit much.