These pads are sometimes needed to change the weight distribution, usually in the forefoot, to transfer the pressure to a different spot.
Here is a metatarsal pad from a local drugstore made of silicone, for under $10.
The best position for this pad has to be decided by the patient.
Too far towards the sensitive area will cause more pain, and too far away from the painful area will not give relief.
The metatarsal pad transfers the weight away from the painful area.
Here is a link to some commercially available pads, which the Hapad company (hapad.com) uses for neuroma treatment, and perform the same function.