Same terms as above apply to these.
Drop Box Files (Vector and Transparent PNG) Find the larger versions and original files here.
The images were made in Inkscape, a free vector program. The transparent PNGs are also available. (edit: I added in a SAI version).
With the islands, it's not hard to shove the islands or ponds together to make new shapes. If you have Inkskape, it's also easy to recolor the fill and lines (changing island to pond or vice versa).