Looking for a piece of sapphire rough

I'm searching for a large piece of sapphire rough, preferably about an inch or so in the longer dimension. It doesn't need to be particularly clear or high quality, just a bit blueish and good enough not to fall apart when worked with. Preferably unheated.
Any advice where I could find it? I had a look at several sellers on eBay but they sell either very small stones, or heat treated material. Mostly they just express the dimensions in weight (carat) not in cm or inch, so I have trouble imagining how large it would really be.

Does any forum member trade with such material? What are the usual prices for such (not prime quality but still unheated) material?

Thanks!