Yes, the A3 as an upgrade is an extra $35.00, and does not include the carry handle. Keep in mind that an upgrade cost figures the additonal paperwork and shop time to switch out an upper. Believe it or not, A3 uppers cost me more than A2's, as A2 forgings are more readily available and cost less.
The 16" bull is the only 16" or shorter barrel I offer with the 1 in 8 twist. The upper you're interested in is not available with a 1 in 8 twist.
Current delivery times are about 2 to 3 months right now.