Hello, I'm Dr. Deb and will do my best to help you.
Thanks for the pictures of your dog's eye. What I see is the third eyelid which is a little more prominent that it might ordinarily be. This might be related to allergies although it could also be associated with mild irritation or possibly other conditions.
Licking his feet, however, might be associated with an allergic reaction to something in his environment.
I have several suggestions which may be of help if this is the case:
1. Over the counter Benadryl (Diphenhydramine) can be given which may reduce his licking....and help if he's rubbing his face or eyes. The dose would be 1 mg per pound of body weight twice a day with sedation a possible side effect.
2. For his eyes: When it comes to over the counter, antihistamine eye drops for dogs with allergies (similar to humans), there are several options. Cromolyn Sodium (onebrand name is Opticrom) is one of those options and can be used in the dog. These medications are considered mast cell stabilizers and can work reasonably well to prevent allergic conjunctivitis if used before exposure to the allergen. They aren't as useful after symptoms have already developed.
Another option is Ketotifen and may be more effective for this condition. Brand names are***** or Zytrec eye itch.
I dose 1-2 drops 3-4 times a day for 5-7 days.
I hope this helps. Deb