WHO CAN RECONDITION MY R80 G/S GEARBOX ?

[EL MEXICANO]

HOLA AMIGOS : Any advice or tips of who can recondition my R80G/S gearbox  ?????,I am having problems with the first gear and when is in neutral makes a grinding noise. 
Any advice or recommendation will be greatly appreciate it ,I can't live thinking my strong Helga is not healthy. :'(

 

[Chrisl]

 

[Fudmucker]

 

[Stofdonkie]

 

[Dustdevil]

 

[EL MEXICANO]