Take a look at your wall wart power supply and post what voltage it provides the dat. I'm wondering if these linear power supplies will work
http://www.jameco.com/webapp/wcs/stores/servlet/StoreCatalogDrillDownView?rf=1&history=0cnb4h2u%7CsubCategoryName%7EAC-to-DC%2BLinear%2BRegulated%5Ecategory%7E4535%5EcategoryName%7Ecat_45%5EprodPage%7E15%5Epage%7ESEARCH%252BNAV%40hh0p1top%7Cposition%7E16%5Erf%7E1%5Erefine%7E1%5EprodPage%7E15%5Epage%7ESEARCH%252BNAV&position=1&refine=1&langId=-1&catalogId=10001&storeId=10001
Would work
http://www.jameco.com/webapp/wcs/stores/servlet/StoreCatalogDrillDownView?rf=1&history=0cnb4h2u%7CsubCategoryName%7EAC-to-DC%2BLinear%2BRegulated%5Ecategory%7E4535%5EcategoryName%7Ecat_45%5EprodPage%7E15%5Epage%7ESEARCH%252BNAV%40hh0p1top%7Cposition%7E16%5Erf%7E1%5Erefine%7E1%5EprodPage%7E15%5Epage%7ESEARCH%252BNAV&position=1&refine=1&langId=-1&catalogId=10001&storeId=10001
Would work