hello! welcome to Seattle and welcome to BP.net! that BP doesn't look too bad but i'm glad u could take it in. i'm sure it is better in your more experienced hands rather than some uninspired kid.
good luck and i hope u enjoy the forum.
Edit: anyways for live feeders - there's The Little Amazon in the north end of the city as Sunnie mentioned above and Sierra Fish & Pets or Midway Tropical Fish & Pets in the south. Petco and Petsmart sells them too, but they make u fill out a pet adoption form or something (even if u intend to feed off the mice/rat). farther north, there are dedicated reptile shops like Hewitt Reptiles in Everett and Reptile Snack Shack.