I would guess you are looking at Service Rifle uppers. We do a fair amount of business with CLE for barrel work. They are not known for fast, but they are known for good. Call Crystal and ask, but my guess is you are looking at 3 months.
all of the good ar builders are out always on lead times. dtech is out 6-7 months currently on a 6mm arc upper. it’s worth the wait though. my 223 and 260 compass lake rifles shoot amazing.