In reply to WildCamper:
Thanks for the replies. I must have clarified that I live in India now, though I learnt climbing in UK. Here 10$ is lot of money. A couple of us are trying to promote climbing in our small town. Not just kids, even for adults. We don't want to give them real rock shoes.
So, it is in that context we are thinking of canvas shoes+cycle tube. Can do it at 1$
. So, I just went ahead and purchased a real tight canvas shoe for myself. It is the rubber (and glue as well) that I need to experiment.