Great idea Muser As long as you are doing it just for YOU and not to just be unavailable...
Have you considered getting another dog? not a replacement.. nothing replaces the loss, just someone who will wagg their tail and show unconditional affection?

One other idea (but coming into winter might not work)... become the local dog walker for the neighbouring dogs? You already do the hard yards in the morning on your walks... you could share it with someones beloved pet that doesn't get enough exercise.