Why not go to sea with it? There are pipes inside that you cannot be
seen. Somebody once said a sleeve is the best repair.

No, the best repaire is a proper unbroken boom! The crack is NOT even! Clearly
COMPRESSED at the top and pulling apart at the base.
Have another look!

http://www.homestead.com/captneal/files/Boomrepair.jpg

Sorry to rain on your parade, even if said parade is very cheap sails on
damaged spars!

Capt RB
C&C 32
NY