Where can you get ammunition for a Winchester Model 1903?
In your dreams! This was the only firearm ever chambered for the 22 Winchester Automatic Rimfire and these cartridges have not been made since 1932. Since it is a rimfire, you can’t even get brass and load your own. You might be able to find a box occasionally from someone like the Old Western Scrounger. Is it worth $5 or $6 a round to hear the old lady go “boom”?