Can he eat alright with the cone on? My cat had a surgery and had a cone and couldn't reach the food bowl because of the cone. I was able to turn the cone around in the other direction pointing toward the rear of the cat. She still couldn't lick her stitches so it worked out ok.
My cat had one of these on because he kept chewing on his IV...he put the cone over his bowl and was able to eat. You couldn't see his head or the bowl, I had to giggle. Then I took pity on him and fed him by hand...Hope you're kitty feels better soon.