I would think a 357 Sig should be PLENTY for anything you'd run into under 300 pounds at 50 yards or less....bears on the other hand....spray and pray I suppose...!
As far as holsters go, I love small leather holsters and because of this I'm a big proponent of Bianchi's Minimalist line. In your case however, their 13/15 sizes specifically say "NOT FOR SIG 2340s!" on their website (http://www.bianchi-intl.com/product/...TxtModelID=105) so my recommendation would be to hit your local outdoors/firearms store with your weapon and ask if you can "test" a Bianchi Minimalist in size 14.
I am assuming your local stores would have these in stock; both Bass Pro and Cabela's stores in the St. Louis area have Minimalists onhand in ziplock bags from the factory; I can't imagine they'd refuse a test drive for a potentially buying customer. After all, the p2340 isn't a production model anymore. Also, the Mininalist sells locally for $45, which is a steal for a quality leather holster.