Building an AR - What parts am I lacking?

[jvtiii]

I've got the following parts for an AR build:
Lower receiver with LPK and grip
Stock
Upper Receiver
BCG
Charging Handle

I know I need a forearm, gas block and barrel but I'm not sure on what other parts I'll need.

Any help would be appreciated!

Thanks

 

[Highcotton]

Good trigger, scope and mounts?, stock configurations, front sling mount 2 if you want to use a bipod also.

 

[DnPRK]

Does the stock have the receiver extension, buffer and spring?
Does the upper receiver include the door/pin/spring, forward assist assembly and sight?
Most barrel assemblies do not include the flash suppressor and crush washer.

 

[jvtiii]

Picked up a complete stock so I'm good to go there. Upper recvr has everything as well. Basically now I am lacking any forearm, barrel and gas components. I think I got her all figured out though.

Thanks for the info!