what's your mast height? Harbortown marina doesn't require any bridge transits, lots of slips and probably room in the summer - also has travellift, and fort pierce city marina is big and pretty nice (fixed bridge 65 ft). There is another marina east of there on the island as well.
Maybe it is further south than you want to be but I have a private dock for rent in Manatee pocket in Port Salerno. It is a couple of miles to the St. Lucie inlet. Full disclosure... 5.5 ft may rest the keel in the mud on lower low tides.