look at numrich.com
I just rebuilt one for my cousin. look at the model 71, also look for "favorite"
I am not sure they have replacement barrels, but I would call someone like Wisners or maybe look on gun-parts.com.
There are a couple of those type of shops that either custom make parts/pieces for older guns or they simply buy broken/beat down for parts to resell.
Check out www.savageshooters,com someone over there might be able to help.
Have you actually checked with a smith yet on buying a blank?