I had my rear 2.5's rebuilt by
DC Shock Services offers valving adjustment, spring replacement, shock servicing and much more to satisfy all your off-roading needs. Now in two locations and providing appointment based tuning services.
www.dcshockservices.com
(a very reputable shop) last year, I think it was $175 each, and they polished them as best they could. The shock shields had to be replaced, so that was another $50. (They also upgraded those weird Fox valves with regular Schrader valves).
The Gen 2 3.0's were a "barely used" set on eBay that were probably $600/pr, but they were ready to just bolt up. You might need to adjust the parking brake cables to keep them from rubbing the bigger shields, but the other problem is the Gen 2's are definitely
longer, and you may need to do the KHC shock mount replacement to move the upper mount a little higher and avoid bottoming out the shocks on a hard landing.