Hi Sue-welcome to the Board from Southern California-sorry don't have a Viking, but no doubt someone here will or steer you in the right direction. A Very helpful bunch here!
Have a Viking...and I think you said you were looking for a walking foot in your other posting...I commented there...go to Husq Viking website...contact your nearest dealer...
You might try ebay. I've been able to find different feet for featherweight that way. Also battery replacement for outdated cordless drill, etc. Just a thought.