Yes, the feedneck can be changed.
Lips carry clamping lever ones I do believe.
You can also get a Newton valve kit, but the stock one works lovely anyway.
Also CP do a reg adapter and different regs to mount on it, but the stock one gives me +- 3 FPS fluctuations, so changing the reg is unessecary.
This is a brilliant gun, and it has the only ups it would ever need (Board and trigger)
When you get it, it will be ready to go and I think you will find it shoots so nice you wont want to change it anyway