I've looked at possibilities for using paper mache for the basic form, it seems like a good idea (Using a kind of wire for the mold would seen to be my best bet). I'm not sure I have the skill (or knowledge) necessary to work with an advanced product like MoldGel, but the final look some of the work I've found using that were very good!
Sadly, I'm still looking for possibilities regarding an arts/craft store, I live in the boonies, and the craft store that was on my street closed last year, I've been looking for another such place with professionnals, but I seem to fall more on places axed towards art via paint only. However, the search is still on!
Thanks for the input