When a new publisher prints an out of print book does the new publisher need new ISBN numbers?

Yes The digits after the country/language designation indicate the publisher





5.1. General


A separate ISBN must be assigned to every title, or edition of a title by each publisher, but NOT to an unchanged impression or unchanged reprint of the same title in the same format by the same publisher. Revised editions require a new ISBN. A price change does not call for a new ISBN. Changes of the format induce a new ISBN. The same title being published in a series and individually is treated as two different editions.