Here's a few sources for aftermarket parts for the II suspensions for street rods.
http://www.totalcostinvolved.com/index.cfm
http://www.chassisengineeringinc.com/index.html
http://www.fatmanfab.com/
http://www.posiesrodsandcustoms.com/posies-catalog/
I looked through TCI's site and they only show one back as far as '35.
http://www.totalcostinvolved.com/productdet.cfm?prodID=521
Chassis Engineering lists on but it is for a dropped I-beam and hooks to the batwings on the 4-bar setup.
http://www.chassisengineeringinc.com/page40.html
Here's some universal sway bars you may want to call and find out about.
http://www.chassisengineeringinc.com/page8.html
These aftermarket sway bars appear to have arms that are shorter then the factory Mustang II units, but I don't know if they are short enough for your Model A. Might wanna give either company a call and see if you can get the dimensions from them and see if it might work. I'm thinking just about
any front sway bar is gonna be out of the question on an 'A' just because there isn't a whole lotta room ahead of the crossmember and even if there is it will hang out in front of the Radiator shell and look gawdy. I don't know of any rear mount front sway bars and I'm thinking it's because of the engine's oil pan or the engine itself would create clearance issues. Trying to recollect if I have actually
seen a front sway bar on a Model A with II
suspension.
Now if you were to fab up a frame horn apron, like the 1932s, '33s, '34s have, you might be able to hide the sway bar under it. But it's might look out of place on a Model A.
Hope some of this helps you out. Good luck.