Hola cenachero, me parece que la solución de sustituir el rodamiento debería ser barata, si ves que te va a costar más de lo que consideras mira otras opciones como ésta:
http://www.ebay.com/itm/NEW-Starter-...7a34f9&vxp=mtr
US $62.62
NEW Starter Volvo Penta 4.3GL 6cyl 2001 2002 2003 2004
Product Description:
Replaces Part Numbers & Specifications
Delco 9000884
Mercury 50-822330A2, 50-807907
Volvo Penta 3860764
Will also replace these older style 10MT Delco starters
Mercury 50-12121A2, 50-12177A2, 50-712428A3, 50-812604A2, 50-99418A2
OMC 984456, 986505, 3850525, 3853982, 3855177
Comes with mounting bolts - Offset bolt pattern. - This marine boat starter fits nearly all Mercruiser, Cobra, Yamaha, Volva Penta, and OMC GM engines except the 3.0 liter.
This permanent magnet high torque gear reduction starter will also replace the older large style 10MT Delco starters with staggered (offset) bolt pattern! It provides higher torque witH less drain on your battery. This starter has an 11 tooth pinion that will replace the older style 9 tooth models.
Comes complete with solenoid and mounting bolts!
Fits Merc, OMC, Volvo V6 & V8 engines- GM Block using a 14.5 inch flywheel.
OEM(s): Delco, Mercury Marine
Type: PMGR
Voltage: 12 Volts
kW: 1.7 kW
Rotation: CW
Teeth/Splines: 11 Teeth/Splines
Pinion/Splines OD: 29.5mm / 1.161in
DE Housing Number: 371-12182
Mounting Hole 1: 10.0mm ID Unthreaded
Mounting Hole 2: 10.0mm ID Unthreaded
New or Remanufactured: New
Approximate Weight: 9.435 lbs / 4.29 kg