I'd get a plastic bag and cut a small piece off it. Apply a small blob of silicone sealant to the bag (about the side of an eyeglasses nose pad, then pick it up and carefully apply it to the glasses (perhaps hold them in a vise, or stick them into something, like a potato, so that they don't roll around and are fixed in such a position that the bag/silicone is resting in place
Wait for the silicone to cure, then peel the bag off it, perhaps with the aid of a scalpel. You should be able to replicate a resting pad, and if you can get the silicone to wrap around the peg that sticks out of the glasses, it will be quite secure.
Elmy was concerned in the comments that the silicone might stick too well to the frame. If you feel this could be the case for your frame you could consider the alternative approach of finding some fine wire, making a sort of drawing pin shape with it - a few turns of wire in a circle and two wire legs sticking out, then embed the wire in a small dab of silicone (with the legs protruding), wait for the silicone to cure and then attached your lifehacked pressure pad to your glasses frame using the bendable metal legs. Because the silicone is already cured it wont stick to the frame, and retention will be via the legs, bent/tied appropriately and cut to size.