duck pit blind

Hi all, I'm looking for a duck pit blind.....you know, one of those blinds that you sink in the ground for duck hunting...

Any of you guys know who handles these?......especially in the Dallas/Fort Worth, north central Texas, or east Texas area...or am I going to have to go out of state to find one.

Been looking, but nothing so far.....had thoughts of building one....but don't know the best way to make it water tight and easy to maintain.....

Jim, in Navarro County, Texas

take a look at
http://www.duckblindsunlimited.com/blinds.htm and you should be able to get something that will fit the bill.