PR-24 is the trade name of a specific side handled police baton, which only resembles a tonfa in shape, not in detail or design...
Many tonfa techniques won't work nearly as well on a sidehandled baton, and trying to use a sidehandled baton in pairs like a tonfa, may allow for some visually appealing twirling, but a lot of the police techniques are designed for use in a non-tonfa fashion, if that makes sense.
Anyway, books on basic and advanced PR-24 techniques are available.
One author is Truncale, another is LeBell.
Take care
Paul Nunis