No problem! I have looked everywhere for these type of tubs and even contacted the manufacturer for retailers then I stumbled upon a vague post on another forum that lead me to homehardware!!
Good luck on whatever you end up building. You will fall in love with racks immediately. They are so easy to maintain compared to what you have now and the watering system makes life so easy. 1 Small tip, if you do go with the watering system (it sounds like you will) add a tiny bit of bleach about 1 cap full for a 5 gallon bucket to your water supply to keep everything clean. I didn't figure that out until after I had to clean the slimy water lines and plugged up valves.
Richard