"IF" he could find the right person tp do it the bores could be "Freshed" to take .311"-.312"m bullets ala muzzle loader style & not have to be Bored. This of course assuming that enlarging the neck by only that amount would clean it up.
I do not know who might could do this work or what it might cost though.

Not that many of those Hollenbeck drillings around, shame to lose it if can at all be saved

Miller/TN
I Didn't Say Everything I Said, Yogi Berra