pmcfall,
I'd go along with the idea that your first 25-20 should be the Repeater cartridge. Shells, dies, etc., range from easy to get to dirt cheap, depending on where you look for stuff.
Be warned, though, that small .25's (and even medium ones, too!) can get addictive! The victim, after using whatever .25 he has for a while, begins to doubt the conventional wisdom that they are all basically the same as far as shooting qualities go. Besides, the .25-20 SS looks a lot sexier than the squatty .25-20R, and wouldn't the gang at the range gawp if he showed up with a box of straight-cased .25-21's to shoot! Soon, the tortured soul begins poring over CH-4D and Huntington's catalogs, rummaging through his collection of shell holders to see if he "already" has one that fits. As the grip of the obsession continues to tighten, he invests in more and more powders and primer brands as he tries, with each shell and each loading, to shade the group made by the last load that teeny fraction of an inch that will show the new shell is, actually, the King of the small .25's. (And don't get me started about bullet mould designs!)
Ultimately, emotionally codependent upon a shelf full of dies and moulds, ammunition boxes full of shells and loaded ammo, a safe full of .25-cal rifles and a notebook full of load and shooting data, our unfortunate has no recourse but to find a support group to ease him of his woes. Like this one, for instance.
Don't ask me how I know this

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