This rig uses a commercial dinghy/canoe sailing sail that I purchased off  ebay.   I have yet to identify the manufacturer.  The sail area is about 40.5 square feet.  It is not reefable.

The mast is sectional aluminum mast pieces from Chesapeake Light Craft.  The sections are sized to fit through the back hatch of the kayak for storage.

The boom is an telescoping aluminum boat hook from the boat store.  The telescoping ability allows for the boom to be stored within the boat.

The outrigger amas and akas are from Folbot, and are attached to the boat via a homemade saddle behind the cockpit.  From ama to ama, the aka is three sectional pieces, using a lock like a take apart paddle to lock the sections to each other.  The middle section is U bolted to the wooden saddle.  The saddle is mounted between the rear of the cockpit coaming and the front of the rear hatch.  It is shaped to the curvature of the deck, and attached via wharram type lashings to deck fittings.

Usually I sail with a leeboard that hangs by rope off of the mast step.  The water pressure keeps the leeboard in place under sail.  In the middle photo you can see the leeboard hanging from the mast step.  The board is weighted with lead at the lower end to help keep it from floating up.  The leeboard does have positive buoyancy so it will not sink if detached from the boat.  The board is made from 1 inch thick oak 10 inches wide, shaped to have a airfoil cross section. 

In the bottom photo you can see a leeboard saddle that I made.  While this works better for sailing, it is a lot of equipment to have on the front deck if you are planning on paddling.

The middle photo also shows the extension I added to the stock kayak rudder.  The extension is made of epoxied marine ply, and is bolted with wing nuts to the stock rudder.  The extension gives more surface area to the rudder allowing better steerage, particularly when using large sails in higher winds.