I found the T bar in the off cut bin at a salvage yard in Port Kennedy, Western Australia. Sorry I can't be more helpful. It's a common profile, you should be able to find a supplier or a user who generates stainless or aluminum offcuts near you. If all else fails any welder could easily fabricate something similar.
Also, you could use two pieces of angle profile back to back, possibly rivet them together? Or cut one end off an I (capital i) profile.
http://www.extrude-a-trim.com/aluminum- ... inum-t-bar World wide shipping, will send a free sample with a small postage fee.
http://www.brunnerent.com online mail order business, under Boat/RV, they have a T hatch molding, part number M4225L. The dimensions are OK not sure about the thickness of the material.
Or look at their Aluminum corners, Capital T, stock#T42416 1.5 x 1 x 1/8".