The Acerbis numbers on my stock '08 screen are: 2407 and AS-6/7 DOT-775 AC 1001. Hope this helps.
Triumph number on the inside of the screen is: 2301606
I run both a Powerbronze double-bubble and a MRA Vario screen, with the Vario being my choice for winter riding. It directs the air flow up higher on my chest and neck. It also smooths the airflow making for a lot less buffeting. If this is what you are looking for, I would think about mounting a Laminar Lip to the stock windscreen for a lot less money.
Springtime is in a couple weeks and I just put the Powerbronze back on. It's 1 1/2" higher than stock and it looks so cool!!!!