I bought mine from these guys 2 years ago :Motorcycle Covers, Bimini Tops items in North East Harbor store on eBay!
and it's held up great. ~$130 with free shipping. It goes together with the spring buttons too, but I've never thought of taking it apart. It's lived on my boat since new. I made diy sliding rails and they make it way easier to rig, especially for overnighters.
I used small cheap carabineers for attachment of the 4 straps to the boat - easy on easy off. It's interesting to read that people are replacing the thinner straps with heavier ones - I don't understand that. They don't need to hold up an elephant and if shit really hits the fan I think I'd them to break. Just my 2cents.
Cam buckles in line would be nice for adjustment and an additional way to release a strap if something goes wrong.
There are numerous other threads on the subject if folks are still looking for more ideas.