Shipping being prohibitive (cost,possible damage),the best place to look is shops specializing in marine fish/invertebrates... they usually come closer on stocking/special ordering acrylic tanks than a general pet shop.
If you feel "handy",and are the DIY type,you could reasonably build your own with info from sites like GARF http://www.garf.org/tank/buildtank.asp ,which also has info on building a stand.