I have only seen one deck repair job and that was on a Pacific Seacraft 31.
The repair was done from above and was undetectable afterwards. The shop
that did the repair looked at doing it from below and decided it would be
easier done from above.

I have replaced keel bolts. The labor cost (exclusive of hauling charges)
was about $500. So dropping the keel and rebedding the joint should be
similar.

David