Since the neck joint failed (if that is all), it should not be that hard to
repair. If you want to change the neck angle, you can cut the fingerboard
through at the 14th fret (I assume that is the body join position). Now you
can clean up the joint, set the joint angle and use slow set epoxy (not the
5 minute stuff) to re-set the neck at the correct angle.
A more difficult problem is when the neck moves and shears the top off under
the fingerboard.
Have fun. You have nothing to lose. If you are too nervous, have a repair
person do it for you.
If you like the guitar, it is worth the effort.
Dave Hajicek