The .38-55 isn't as unusual as it used to be. Epp's lists the brass. They likely have bullets too. Shooter's Choice, in Waterloo, likely has both as well. Goble's, in London and Tillsonburg, lists brass. $28.50 per 50 for Winchester brass. Most likely have bullets too.
I have some data, but data isn't hard to find either. There's cast bullet data on Hodgdon's site.