Hopefully this will work for you. If I read correctly, you just want to be able to recreate this shape at any size so that it always has straight edges and no pixelization or jagged edges.
Part of the problem, I think, was that your shape wasn't completely symmetrical in relation to the y-axis (I'm assuming here you expected it to be). In other words, if you cut the thing top to bottom, that the left and right would be exact mirror images.
Anyway, download the attached PSD file and open it in Photoshop. Click "Edit, Define Custom Shape..." and give it a name. In whatever new image you create, use the "Custom Shape" tool (ninth button down in Tools). In the Options toolbar, click "Create Filled Region." When you create your shape, make sure you hold down [SHIFT] so that it stays proportional, and that the Foreground Color is set to what color you want to use. And for each of the six instances, create a new shape; don't copy the layer and resize it, or you'll still get jaggies.
BTW, I used this tutorial here:
http://www.melissaclifton.com/tutorial-pentool2.htmlTook me about five minutes.