Monster Tower Bimini?

Anyone figure out how to modify or buy a cheaper Bimini? I had my bimini all set, and modified tow work, then I found out the local canvas guy would only modify my top for a mer $200! Bummer... so now Im back to square one. I have see quite a few on the Net, but to me it seems like any bimini that could attach to the tower legs would work right?

If you have an ideas, holler!

Thanks much!