Keith,

Couple of possibilities.  You might check Backyard Bees of Bend, Kim Rivera (a member), or Liddell's Honey in Sisters, or Tumalo Garden shop, or Coastal (used to be Big R in Redmond).  Else, depending on how many you want and whether you want parts with assembly, or assembled frames, my favorite is western bee supplies, manufactured near Kalispell Mt.  My next favorite is Mann Lake LTD. also for either one.  With either, you need to read carefully both the sizes, as well as the type of top, bottom and sides, depending on the type of foundation you're using.

Good Luck.

Allen Engle