Ok there's irony here in that the site says "environmental" and it's made out of plastic.... oh, yeah.
Yes you could make one yourself. Here, the lumber yard gives you one free cut. Buy a 4 x 8 piece of plywood. Have them cut it to 4x4 pieces, then pay to have one of them cut into two triangles. Then you go to pipe - PVC, copper, or aluminum and the flange type fittings (I think that's what they're called) to bolt the pipes to the board (you may want to get a large pipe cutter to cut the pipe to size.) I think you can figure out how to put it together -- and customize it to the height you want.
And paint it the color you want.
and curse me for suggesting it because it will be heavier than what you would like.
But hey, you can manage.
You could also build it from rescued pallets. But you would have to do the cutting yourself...