It appears to be the next opening south of the rasin river, am I correct?

Yes that is correct, just be sure to stay out a bit and line up for a straight in approach, it is shallow on both sides but plenty deep in the middle.

how far out do I need to stay, thinking of checking it out saturday, is it rockey in the area or sandy, don't want a "rock fish" to get me

I will be blasting around the Wolfe Island/Cape Vincent area this weekend, IF I can get impeller changed by then, anyone in that area gonna be on the water?

If you look at the pic you can see the rock shole on the north side, it is probably 300' feet or so out so as you are coming in from the lake just line it up for the middle and you are good to go. it is best to either beach up on the northern part of the sand bar or drop anchor in the lagoon, the water is a steady 83 deg, kinda like bath water or better. We might take the skiis out sat if it is not raining, we will be on rxp 255's.