I use a very nice Chinese 43mm vented-tilted CNC-machined lens hood designed for wide-angle lenses and which is a copy of the Leitz 12504 hood. NB : it is wider and shorter than the current vented-tilted replicas of the Leitz 12585 hood.
It's a perfect fit for the W-Nikkor 28mm f/3.5 in S-mount.
Yes the front element of this lens is recessed enough but the hood will be useful for two important things :
- it will protect the lens from dings and will allow you to travel without any valuable and original NKT front lens cap (you can put a generic 62mm clip-on lens cap on the hood itself if you wish),
- the hood will save many pics of yours as it will not allow your fingers to be in the frame, which happens very often when you use this lens without any hood and grab it with your left hand to focus and hold the camera unit.
I bought this excellent hood for a few bucks on the 'bay.
Example : item 153527185444 (no connection to the seller).
You can also use the rear part of the two-parts 43mm original alloy Nikon hood designed for the Nikkor-S-C 50mm f/1.4, if you are lucky enough to have one.
The NKT hood on display on the mir website also uses this rear part from the old alloy 43mm Nikon hood, with an original add-on for the 28mm lens.