Lyman makes a GPH (Great Plains Hunter) barrel you can buy separate directly from Lyman, $179ish US dollars. Same size as the GPR, but a 1:32 twist I believe, if you really want to go with two different barrels.
For sure easiness though, I think I would have to agree with the above gentlemen and say the Hawken that will take both, because of the twist. :winking: