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I would just get yourself a Lee four-hole turret press, a set of Lee dies (no, I'm not a Lee salesman - their stuff is just good, reasonably priced, and that particular press I the bees-knees for not only starting to reload, but experienced reloaders doing higher volumes, because it allows the processing of your reloading as 'single stage' OR 'progressive' so is useful for running a few test-loads OR several hundred).
http://www.MidwayUSA.com/ has the best prices and good availability. Get a basic reloading scale, cheap plastic reloading tray to hold cartridges, and whatever powder measure you like (or just use 'dippers' - a set costs ten bucks or so and they really DO work well and are pretty non-controversial). You'll be reloading in no time.
As far as right NOW, you may have to look on
http://AmmoSeek.com/ or even
http://www.GunBroker.com/ or
http://www.GunsAmerica.com/ for ammunition or even brass. Get it while you can. AmmoSeek shows Cabela's does have Buffalo Bore loads
in stock (
dunno if you'd want 255 JFN @1950fps in that gun or for your purposes) at the moment, but listings change frequently.
I think you may be able to use 375 Winchester
brass in a pinch, though the headstamp would be wrong.
However,
MidwayUSA shows Starline 38-55 brass as "in stock" at the moment in both 2.082" and 2.125" lengths:
Lots of powders available for that type large straight-wall case -
http://AmmoGuide.com/is a
good and affordable 'reloading guide' that compliments a written manual like the Lee or Lyman with up-to-date load data from both consumer and manufacturer in a VERY easy-to-search site with lots of tools for load comparison, "what-if's" about powder and cartridge combinations, etc...
Stock up on components - you can never have too many. Powder and Primers are fairly 'generic' anyway, so 'overstock' can be used on another cartridge. (
AmmoGuide has great tools for helping decide the most strategic powder to stock extra of, for whatever cartridges you want to reload for).