Make your own.

Not hard to build and 3 home made ones will cost about the same as 1 brought one.

I built mine out of a 55 gallon drum a boat winch 3 12' round gal corner posts, made a base plate for the legs that the winch cable goes through and 3 6' t posts to secure the legs to the groung.

This pic was taken before I put the boat winch onand secured it with t posts.