Redhawk,
There's a guy named Bob Day in Pico Rivera, CA that advertises this work. Also, you might call one of our members that specializes in bore work, Mike Orlen in Amherst, Mass. 8" at 25 yds is about 1/2 a degree angle. Seems like a lot, especially for a 410, but these guys should be able to assess if this is a fixable condition.