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.

Regards,
Jon Page,   piano technician
Harwich Port, Cape Cod, Mass.
http://www.stanwoodpiano.com/