US Airways scope currently allows
175 aircraft in 50 seats or less,
212 aircraft with 51 - 70 seats,
153 aircraft with greater than 71 seats.
US Airways can have 540 regional aircraft and American has 255 aircraft (included are AE and Connection). There are already 795 aircraft allowed.
If Parker exercises the options of AA, there are over 460 new aircraft coming from the AA side not counting the 787 and 777 still on order.