Since your gun doesn't have an accessoryrail, you'll need to go with an internal laser or one that clamps on in some other way.

Lasermax, who make the recoil spring guide rod replacement lasers, does not list a product for use with your gun. For Taurus/Beretta, all they have is...
Full Size Beretta 92, Beretta 96, Beretta Vertec, Taurus PT92/99/100/101
http://www.lasermax.com/product.php?id=16

Crimson Trace, the makers of Lasergrips, only lists lasers for Taurus Revolvers. http://www.crimsontrace.com/Home/Products/Taurus/tabid/200/Default.aspx

I don't have an easy solution for you, since other attachment methods usually make holster carry difficult or impossible. On the bright side, both companies listed above are always looking for feedback on which models of guns they should be making products for, so make sure to give them a call or write.

Good luck.
-Bulz