[knothead]

I would suggest that you make your own. There is nothing complicated about lazy jacks and you can save a lot of money by fabricating them yourself.
I would also suggest that whatever you decide on, you have the kind that you can lower so that the sailcover can be used without having to be modified. Also, I have had good success installing lazy jack from a block hanging from the bottom of the lower spreaders. This is better than a cheek block attached to the mast in that it creates a vee that makes it easier to get the main sail headboard past.