I dive from a "cheapy" pelican tandem yak, that I bought in Galveston, while I was a student @TAMUG. It is a sit-on, but they are really the only thing to dive from. Why do you think your yak won't do for diving? If it's stable, will hold you and your gear, and can be paddeled without too much effort, it should do fine, or is it a sit-in?
Alhambra Beach is in Venice, here are the directions:
Venice Beach
Dive Spot: Venice Beach, FL
Type of diving Shark tooth and fossil hunting in the Gulf of Mexico. This area is a prehistoric river bed and does yeild more fossils than the sharks teeth.
Type of diving: Shore dive
Directions: Google Maps
I-75 exit 200 to Osprey.
Continue Southeast on TAMIAMI TRL N/FL-45 S/US-41 S toward BAYVIEW DR. Continue to follow TAMIAMI TRL N/FL-45 S. 7.4 miles Map
Turn RIGHT onto MIAMI AVE W. <0.1 miles
Turn LEFT onto NOKOMIS AVE S. <0.1 miles
Turn RIGHT onto PONCE DE LEON AVE. 0.3 miles
Turn LEFT onto HARBOR DR S. 0.1 miles
Turn RIGHT onto ALHAMBRA RD. 0.4 miles
Follow ALHAMBRA RD to the end
What to expect at the dive site: Typical sharks teeth found are from the folloing: Dusky and Blacktip family, Sand Shark (current and prehistoric), Bull Shark, and Lemon Shark. More rare but also found are Mako, Great White, Snaggle Tooth and Megalodon. Other fossils that can be found include dolphin, manatee, and whale bones, stingray stingers and crusher platelettes and tail vertabrae, porcupine fish platelettes, mammoth and mastadon teeth/tusk/vertabrae, sloth claws, alligator scales, and sabertooth teeth. Best times for hunting are a few days after a storm when the water has settled down. Depths are 16-18 feet, unless you swim a long way out then you may hit 20.
Where to park: parking is on the street: do not park blocking driveways or park too close to corners. Park the same direction as traffic flow(tickets get handed out weekly).
Amenities Florida West dive shop is about 1 mile north of the site on 41 literally just over the bridge back onto the main land. Sharkey's resturant is at the base of the pier. Venice Beach's downtown district is 1/2 mile off with food and shops as well.
Pros and Cons When the water is clear lots of teeth can be found. When the water is a milky emerald green, there will be no visibity on the bottom and toothing is useless.