Don't think anyone makes a Type 3 towbar, so you might have to have one custom made.
Found this info on the samba forums :
The super beetle tow bar makes a very good start. You add a single strip of 1 1/2" angle iron to one side, and drill 2 holes in it and bolt it to the bottom of the beam. You add two pieces of 1 1/2" tubing to the tow bar tubes and your done. If you get one of the better ones, they come with quick disconnect pins at the ends. This set up only eats up about an inch to 1 1/2inches of ground clearance, and can be left on all the time if you notch it for the grease zerks.