Treeview arrow indicators

["Philipp E. Letschert" <phil uni-koblenz de>]

Hi,

I would like to have a table where only the first row is visible, with
a triangle on the left, when clicked showing the other rows, and the triangle
changing from pointing right to pointing down.

How can I get these triangle images, as they are not in stock?

Or would it be a better solution to use a real treeview? (But the treeview
should look like normal labels - no borders, default background, no selection,
etc.. is this possible?)

Regards, Phil