You can order on at "real" lumberyard or at your local home center. Just make sure the jamb is 6 9/16" wide (5 1/2" for the 2x6 plus 1/2" of drywall on either side). Either place should give you a detailed copy of the order, double check to ensure the dimension.

Hi, You were recommended to get a jamb 6 9/16 wide . Sounds good but just check you have 1/2 inch drywall and not 5/8. Just an ounce of prevention.

Good Luck Woodbutcher

What if you do have 5/8" drywall?

Special order the frame size as 6 13/16" or 6 7/8".

That isn't at the box stores. Im assuming a real lumber place would be able to order?

"That isn't at the box stores. Im assuming a real lumber place would be able to order?"

Exactly.