The following drywall-type, hollow, metal door jamb sizes are in stock, but additional depths and sizes are also available.

Widths
4 3/4": 3'0" | 6'0"
5 5/8": 3'0"
5 7/8": 2'0" | 2'6" | 2'8" | 3'0" | 3'6" | 4'0" | 5'0" | 6'0"
6 3/4": 3'0" | 6'0"
7 1/8": 3'0"
8 1/4": 3'0"
8 3/4": 3'0" | 6'0"

Door Height
4 3/4": 6'8" | 7'0"
5 5/8": 6'8" | 7'0"
5 7/8": 6'8" | 7'0" | 7'2" | 8'0"
6 3/4": 6'8" | 7'0"
7 1/8": 6'8" | 7'0"
8 1/4": 6'8" | 7'0"
8 3/4": 6'8" | 7'0"

These are designed to be installed after the drywall is in place.
All door frames from Cleveland Vicon are fire-rated and supplied knock-down.