I trust the pins are the same diameter as the originals when measured
with a micrometer. To achieve a tight fit in the rails, swab the holes
with either epoxy or CA glue and let cure. Reaming the hole with a
drill bit afterward may be necessary to get a proper fit. Care must
be taken to maintain the drilling angle.
If the pins were so corroded as to requiring replacement I would say
that the bushings are worn also and should be replaced.
Jon Page, piano technician
Harwich Port, Cape Cod, Mass.