I just scored tickets for 2 people between JFK and Milan for next October. Total cost was $659 using the AARP discount through British Airways. American Airlines and Emirates have similar pricing, but there is no AARP discount.
Interesting, when I looked at the terms and conditions for the AARP discount for BA it indicated that outbound travel had to commence by March 31, 2017.
http://www.britishairways.com/en-us/offers/partners/aarp-member-benefits
If I price the same tickets on the regular BA website, they are $198 each way per person. If I start in the AARP website and click through to BA, the price shows as $165 each way.