I'm looking mainly for thin sheets for model boat-building.

A Google search threw up a company at Minburi called Minicrafthobby.com but their email and phone connections don't work and I was informed when I stopped by their location today that they packed up in the floods.

If anyone knows another source I'd be grateful.

I've seen it at stationary stores near universities. I think I've seen it at the Suksapan store at Future Park Rangsit (there are several Suksapan locations ..http://www.suksapan.or.th/). Its definitely around, my students use it. What I have yet to see though is Basswood for model making..I've never been that satisfied with the texture/grain of balsa wood for scale models. I would recommend that you go to Bang Po (Soi Furniture) and get some sheets of nice veneer. Just laminate to get the thickness you need.

I've seen it at stationary stores near universities. I think I've seen it at the Suksapan store at Future Park Rangsit (there are several Suksapan locations ..http://www.suksapan.or.th/). Its definitely around, my students use it. What I have yet to see though is Basswood for model making..I've never been that satisfied with the texture/grain of balsa wood for scale models. I would recommend that you go to Bang Po (Soi Furniture) and get some sheets of nice veneer. Just laminate to get the thickness you need.

Thanks for all that. I'm making a model to actually sail, so the appearance of the wood isn't paramount as it will be fibreglassed and painted, according to the plans. I think the attractions of balsa are lightness and ease of working. However, when I get a trip to Bangkok I'll certainly check out the locations you suggest.