THE HOME OF SAM HOUSTON’S WIDOW, Margaret Lea Houston, and their eight children is for sale. A shrine of Texana, the 1830's Greek Revival classic in the tiny hamlet of Independence comes complete with a Houston family heirloom piano that is said to render a ghostly “Come to the Bower,” the San Jacinto marching song. The house is one of a handful of Texas buildings of that period on the National Register, but registry offers it little protection from the whims of new owners. And the house couldn’t have come onto the market at a worse time for its preservation through official channels. The Texas Parks and Wildlife Department, the state agency charged with acquiring and maintaining historical properties, is not only not buying but it also has plans to close seven historical parks this December to balance its budget (expected savings, $321,000). Worse yet, Parks and Wildlife officially doesn’t consider the house worthy of preservation. When owners Gene and Frankie Slaughter offered the agency first crack at buying the house, they were rebuffed on the grounds that the building did not qualify as a historic property under the state’s antiquities code. The Slaughters were stunned. Says Frankie Slaughter: “I can’t believe the state values so little the contributions of Texas’ first First Lady.” The only alternative seems to be a sale to an individual. Asking price? $275,000.