You can't afford like $25? A ten foot long 3 in OD PVC pipe will cost you less than $10. Get scrap wood for the frame and some wood screws of about $4. Shit, you could make that by setting up a lemonade stand. Seriously, that's what this cult is all about. Want it? Build it!
To op, the only problem with a single barrel or even dub barrels when you leave space between the pipes is that they tend to break off at the ends. On suggestion I have is to by this product called "Great Stuff". It is a spray foam product. Spray that stuff in both ends of the pipe and it will help keep it from fracturing.