I had Darton sleeve mine. They did a good job, no shifting/sinking or anything like that(yet).

Golden Eagle mfg.
Darton
AEBS
Earls
There are a ton out there, most reputable are of course in cali.
Shouldnt cost you more than a grand shipping included for any of them. Id send them the pistons too so they can final bore/hone while there at it...