These are available from a lot of sources. I have three MNs, all long barrels, and I wouldn't hesitate to carry one as a survival rifle. Just takes a little more muscle.
I bought my first 91/30 online, no C&R required, but it had to be shipped to my local gun shop. I bought my second 91/30 through Gander Mountain (they recently had them on sale for $99). I bought my third 1895 M91 through a local gunshop, and despite it's 115 years, it shoots just fine.
You can find sources for these, and ammo, through advertisers on Gunboards Forum:
http://forums.gunboards.com/
They also have a Mosin Nagant subforum for collectors and tons of information. Just don't tell them you plan to "Bubba" one of these beauties, they will skin you alive
One correction, a counter-bored barrel is not a bad thing. The Finns did this routinely to captured Russian rifles to improve accuracy. Otherwise, you have to worry about dinging up the crown of your barrel. For a survival rifle, a counterbore would actually be desirable IMHO. My M91 is a Finn-capture with a counter-bore and it's as accurate a shooter as I am.
Edit: I also did a similar conversion, like 11x11x did, to a commercial Norinco SKS. I used an ATI Monte Carlo stock and I like it just fine. As 11x11x said, it was a little tight and required a bit of fitting and sanding. This would be my grab-and-run gun.