A group of us IRV2'er (Pond Piggies) did a Labor Day Weekend up at a NY State Park called 4 Mile Creek State Park located about 10 miles north of the falls. That was about 2 years ago. Very nice state park, large sites, most are level, most with solid grass pads, on the shores of Lake Ontario. Here is a link >
4 Mile Creek State Park < They have 275 sites, with a little under half with electric service.