Sliced Sprites as clipping masks

[Megaloadon98]

Hey,
I need to create a blurred UI panel with a custom texture for the alpha to break off some edges. That texture needs to be sliced as a sprite, to adjust properly with different panel sizes. Right now I have no idea how to render the blur effect on custom shapes except for the boxes and rounded corners that are supported. My workaround was to use the clipping mask, but that doesnt support sliced sprites right now, so the texture stretches. Is there a way to either use a sprite mask, or have the blurred background render on a custom alpha texture?

Ill attack some images of what I want to do and the stretching issue.

Thanks!