Can the harmonic balancer be rebuilt or repaired?

Harmonic balancers are replaced when the the bond breaks between the hub and outer ring. Auto parts stores have large books full of replacements for all car brands and engines.

I believe you are refering to the 2.5L engine.

Removal

Loosen power steering pump belt adjusting bolt, lock nut and mounting bolt.
Remove power steering pump belt.
Loosen idler pulley center nut and adjusting bolt.
Remove A/C compressor belt.
Loosen generator belt adjusting bolt, lock bolt and mounting bolt. Remove generator belt.
Hold crank pulley with tools and loosen the crank pulley bolt and remove. (bolt is tightened to 150 ft.lbs so would requires quite some strength to loosen.
Remove the crank pulley.
For installation, reverse removal procedures.