Team C Hyde diff help

[Mark Prior]

Wondering if anyone can help, just got hold of a Hyde stadium truck I stripped down the gearbox earlier as it would barely move and felt terrible, Discovered a melted diff gear, couple of diff balls were wrecked and there was lots of sludge so I want to know what options are there for a geared diff conversion? Just thought while it's in bits should I look into converting? The team c geared diff kit is pretty pricey so is there a cheaper option or should I just replace the melted gear and stay with the ball diff?