my waterer is basically a pass through from rain water.
but for the feeder...without a doubt...you could use a 50 gallon barrel with PVC pipe...and would be cheaper than the $150 i paid. i was actually thinking of using my grain elevator to buy feed in bulk, feed into a hopper and then gravity feed into feeders.
If you used a 50 gallon barrel with PVC pipe for feed, you would have to install a cone in the middle to force the feed to the outer walls. My chickens can get their heads in about half way on the 5 gallon bucket, but a 50 gallon barrel is a lot wider.