Recoil Rob,
You can always go the insert route. MCA will custom make a 22 mag adapter for your chamber.
http://www.mcace.com/rifleinserts.htmlAlso, I believe many of drilling makers offer full barrel inserts as well. Unless of course, you have your heart set on a new drilling.

A .243 would be great round for javelina and serve for antelope as well.
You could look at the Merkel 96K 12x12x243 or the Blaser D99 20x20x222 or the Krieghoff trumpf dural 12x12x270
Speaking of the San Carlos... I came very close to doing a do-it-yourself lion hunt there about a year ago. Seems they have way too many lions. The reservation biologist gets daily reports and she is more than willing to share this information. The fees are some of the cheapest around.
Pete