Would everyone agree that for starters any 30 plus year old boat that was going to be used the way the OP plans should have the following done if it has not been done in the last 5 years and good evidence that it was done right.
1. Drop rudder and inspect and or replace bearings and all linkage.
2. Replace chain plates
3. Replace standing rigging
4. Replace running rigging
5. Check ground tackle and get spare
6. Check sails and get spares
7. Check electrical and make sure lights, pump work.
That sounds like 10k minimum assuming some of the above is OK and some needs doing.