Here are a couple more:
Aug 6 -- Sandusky Steeplechase, from Sandusky to Put-in-Bay, Ohio, 22-mile distance race as feeder for the I-LYA Bay Week Regatta
Dec 10-11 -- 21st Annual Key Largo Steeplechase, Key Largo, FL, 110 mile race around the island with a Sat. nite stop.

Brian Karr would also be a good one to contact on FL distance races.
Rick