I "made" this a long time ago when I needed a stand to hold up Ocarina Tabs that I had printed out. It's pretty effective. One of my friends gave me the stand and I decided to mod it a bit so It could hold itself up. I bent the bottom parts and glued a thin cardboard piece to the bottom to help hold things up. Then I just glued the bottom 2 things to a couple of wooden blocks.
I'm sorry if you came here looking for a homemade stand that you could make as well. Believe me, I tried to make one and it never came out right until I got this piece.
So if for whatever reason you want to turn a sheet music stand-attachment into an almost portable music stand, I hope this helps.