I liked B&HPhoto, but seems their out of stock for that one. Purelandsupply offers a Philips bulb you can get a little cheaper, $178 and reuse your original housing. Or pay a little more for the bulb and housing. http://projectorcentral.com/Sony-lamp-suppliers.htm
Either way, make sure it's a name brand bulb, Sylvania, Philips, etc. no OEM equivalents.