Need eccentric wrench for CA

I'd like to buy an eccentric wrench if someone has a spare.  This is the one that fits a 1/2" square eccentric bolt head.  It is different than a WD or WD-45 which has a hex head.  Any help would be appreciated.  Stories, pictures, and explanation to follow.

You can make one if you can drill a 1/2" hole in a piece of 1/2" steel bar stock. You just need a square file and some time to cut the corners to fit. You can cut or grind the shape of the bar stock to look as close as you wish to the original.  Once in a while I have seen them on ebay but not often. My first CA the wrench was under a seat bolt next to the shifter but the one I have now didn't have one with it.    

Here is a pic of them, the one on the left is for the hex eccentrics, the center is for the CA w/ square head eccentric and the one on the right is for a square head eccentric (came with a D12 I bought, not sure if it is AC).

Eldon, the ones I have seen were die cast steel about 5 to 6 inches long that you had to tap with a hammer.   

I second RMD.  Craftsman sells 1/2 drive square sockets, and they hold up well.  Never broke one turning my eccentrics.  Start soaking now with favorite rust buster.  

Sears no longer carries 8 pt sockets in their stores.  The clerk said to try to find them at their on-line store.  It shows they have them but can't tell if they're 3/8" or 1/2" drive.  Frustrating.

I welded two 1/2 in drive impact sockets together.   (Harbor Freight specials) and it worked great with a breaker bar and a long pipe.  

If you have not moved the eccentrics, or you purchased a older tractor, you almost have to take them off, heat the bolts, and work oil into it.  Then when you put it back together the tool is needed to tighten the bolts up.   Mine worked good.

You can put a 1/2 inch drive extension on it turned backwards,and the big pipe wrench on the round part of the extension.