Don't know about Blue Heron but if they are no longer in business there is a place called Way Fun Kayak in st cloud .
They don't have a website but here's a little bit of info for you
Way Fun Kayak Adventures
Basic Info
Take a guided tour through the untouched beauty of Florida in a kayak for a real back-to-nature experience. Relax and get some exercise as you paddle your way down Shingle Creek or Lake Butler. No engines means no noise - you can get very close to some of the wild residents before they even realize you're there. Don't worry if you're not experienced, the staff at WayFun will show you all you need to know.
It's a very enjoyable day if you like the outdoors and a chance to see what Florida looked like before the theme parks. Probably not a great idea for younger children.
Location: 1670 Sundance Drive, Saint Cloud, FL 34771
Telephone: 407 957 0071 (Call for pricing.)