Rob a few years back my 40 amp alt on STranger karked it. I had it rebuilt at an Auto Electrics shop. They respun the centre and its working juST fine after another 100,000k's Maybe ask about over your way if any Auto Electricians know someone to rewind the centre spool bit and replace anything else that needs fixing.
"the centre spool bit" = rotor.The stationary part is called the armature.
the centre spool bit" = rotor. or ArmatureThe stationary bit is called the Stator