Samson does make upper picatinney rail sections for the Gen 2 RPR in 2", 4", 6" or 8" sections. They are held in by a drilled and tapped bracket which fits underneath and within the curve of the upper part of the handguard. Go to Samson's website - Evolution Accessories: Samson Manufacturing
This will allow you to add iron sights or whatever.
You can buy a complete handguard sans the connectors. Just unscrew your gen 2 handguard and slip it off. Slip on the handguard with the complete picatinney rail and put the screws back in. You now have a Gen2 with the Gen 1 handguard. The handguard is the RTR-15 for $145. RTR-15: Samson Manufacturing