Same site has a complete bike for sale. (with pods though)
https://cognitomoto.com/products/1974-cb750
About weather and pods. I had no problem during the 80's driving in heavy rain almost all day long on Autobahn in higher speed. The rain like real shower and difficult to see anything, especially when passing long trucks that splashed extra. Not even a hesitation, only a stable scream from the loud 4-1.
Maybe my legs with rain trousers over leather suit and boots covered up for the pods, the small conical version. Bike had no fairing either.
The photo below how bike looked like back then. I added a later photo to show the pods closer.
Yeah Pewe, there's lots of "anti-pod" talk here and always has been, but I've still got the old K&N's I bought for my first K1 in 1980, and I really can't tell any difference between them and my stock airbox, apart from the fact that they breathe better, so need bigger jets.
Now I don't get the kind of sh1tty weather that you do, but I rode that bike every day in any weather for 4 years, and my biggest issue when it rained was the plug leads earthing to the frame, and causing it to miss and fart, but I never had a problem with the K&N's. Cheers, Terry. 
OK, bad wires, caps that cause sparks in wrong place. to frame instead of inside combustion chamber. I have had that problem too, but not during an important touring.
Old car and my CB750 with std ign wiring. Cut the wires 1" from coils, crimped new wires and new tight silicone caps. They are visible on the pic, orange caps. Mice had tasted them in the barn.
Maybe some bikes get bad aerodynamics behind engine and around pods or wrong jets that will fit air box better? Or carb dependent, some carbs might work bad with pods. Not my K6 std carbs. No alternative with Mikuni VM29 or Mikuni TMR32. The latter has good flow due to the filter adapter that look like a short velocity stack.
The air box this thread started with look very cool. I understand that some want that design on their bikes.
