A. Assuming only one page is bad, then it isn't too bad. If there are lots then this process must be amended to do random selects above the low key to find the next good page each time.

1) Do a SELECT key FROM table, and note the last key value (low key) returned when it fails.
2) Do a SELECT key FROM table ORDER BY key DESC, and note the last key (high key) again.
3) Create a "dummy" table with the same structure
4) Insert rows into the "dummy" table with key values less than or equal to the low key.
5) Insert rows into the "dummy" table with key values greater than or equal to the high key.