"Available" .40 caliber reloading components...

[MexicoMike]

Concurrent with my interest in acquiring a double rifle I've been doing some research on calibers. My initial thought was for a .470 NE and it's still my main "thought" but I was thinking that looking at other .40 calibers would give me a bit wider range of "vintage" British rifles to consider. But my searching so far has not found any readily available (in stock) .40 cal dies/brass in other than .470 or .450/400. I have seen nice looking rifles in calibers such as 450#2 and other calibers but no dies/brass. Are there other .40 calibers with brass/dies available currently?

I am not willing to order/wait for custom dies or other components so the caliber has to be one for which I can order the necessary reloading components/have them in the normal shipping timeframe.

 

[MexicoMike]

Decided on a 450/400 rather than a 470 - ordered the brass/dies from Midway. Sent two email messages to a well-known double rifle seller several days ago re buying a rifle on his site but no response yet.