try your local agricultural merchant. I was going to buy free standing hay racks but bought sheep ring feeders instead as they worked out better for me as i could just stick a whole bale rather than pulling it off and throwing into a rack
I just use an old water trough in my mare's field. Has a few leaky bits so no good for water any more but stops the hay blowing around the field and getting trodden in - job's a goodun'!
Maybe ask a farmer in your area if he has any old ones that he doesn't need? They also don't blow away, unlike hay hutches can (plus, have you SEEN the prices of them?! Phew!)