I've shot my own TC's and a friend's Rem XP. I would take the XP for consistency. The TC's are inexpensive and can shoot small groups, but they are not problem free (in my experience). For cartridges, I found the 30'06 to be a bit uncomfortable, while I enjoy shooting the .308. Just that little bit of extra recoil pushes it out of the comfortable zone for me (personal preference). I've had good groups with .223, .243, .308 and .30'06. I have also had some fail to fire and some flyers. You might enjoy something like a 7mm-08 barrel, or a 6.5 of some sort.
I bring up the TC's because I think you are more likely to find them on short notice and you mentioned that was important. They can shoot well, but there are some problems with em.
I really enjoy shooting mine with a .223 barrel on it, otherwise I wouldn't still have them. I have to say, I feel like I am recommending a cheap beer to you or something similar. I first got my TC's because I heard of how fun they are with a .223 barrel (they are
). I think if you want a long range hunting pistol, there are better options out there (trigger, fit, consistency, strength). I am tempted (another project) to go with a Savage Target action, and build a long range shooter out of it, but I am not looking at doing that any time soon. I wouldn't mind trying one of the MOA handguns and seeing how well they shoot. If I was looking for a dedicated long range pistol, I would not go with a TC.
If for some reason, you can't find a better gun and end up going with a TC, you might enjoy reading this : http://www.6mmbr.com/gunweek055.html
It is in the rifle config, but it is about the best I have read about someone getting out of a TC encore.
Best of luck!