Hello Roger,
A lost log book can be difficult. The FAA has the last record of flight time on the last 8710 they filled out for a Certificate or rating. The rest will become an estimate. Old days, you would take a new log book and have it notarized. Nowadays, with computers, if anything was on their computer, a read-out would work. In any event, the person should call their local FSDO for their requirements and do as they require.
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