Make them - I built mine for $11 a bucket, which included $6 for the coco coir:perlite media. I use the Lowes buckets, and they are going on their 4th year in full sun. When I bought the buckets they were $4, but they have gone up to $5 now. If you go to local bakeries/grocery stores/restaurants you can find them for free. I don't use lids.
It is super simple. https://www.youtube.com/watch?v=nXy32Dr4Z4A
I use these tophat grommets with a 7/8" hole, 2" from the bottom of the bucket. I clean up and slightly enlarge the hole with a deburring tool, and use 1/2" PVC with an elbow on each end.