The material I think cost less than 15 dollars I think so it wouldn't put you out much.
I just got like 8 pieces of pre cut 3' tubbing
a bag of t's and elbows.
I didn't even glue it.
you will notice if you look carefully, the base width is probably about and inch and a half wider than the top.
I used the same cut outs for the cross pieces but just jammed the top cross holds into the elbows further.