Dig around and find the contact info for Ron Smith, the barrel maker. Give him a phone call, and ask what you need to know. Report back your results.
He has a rep for putting tubes on some of the best guns on the lines, hard and honestly earned.
I read a report a while back that said he daughter (or neice?) shot a perfect score with one of his barrels at a range in Sherwood Park last year. I took that to mean that there is some active shooters there, as this took place in a match.
For them that don't know, the shooting is mainly 200 yard, offhand shooting. A perfect score is really a rare thing.
As to the guns, it depends on the rules you have to shoot under. Pretty much all single shot, non-bolt action guns. Winchester High Wall or Low Wall 1885 actions are a good start, and are pretty available, a Stevens 44 1/2 (not the 44 or Favorite) are also good, and a version is still in production (see singleshotrifles.com) . Then there are the Millers, Yost's and that ilk of low production custom actions (pretty much gotta watch the obits and be the first to be on hand to deliver condolences and ask after the stuff to get, though, if they are not already bespoke...)
Add to that the Ballards, and a bunch of other older types of guns...
Lots of good groups been shot with not very decorated rifles, too. No point in spending a bunch of money on something that will be devalued by wear and tear. You get beat out on the amount of money you want to spend, by someone that buys them as "investments" most of the time anyways, and never wants to shoot them.
Call Mr. Smith. Check out, among other sites, the Wyoming Scheutzen Union site, as well as the ASSRA forum, to get an idea of what is out there as shooting irons go for the game.
Cheers
Trev
(not a Scheutzen shooter, just a fan of the single shot guns used there!)