That's a very good deal. Very strong processor, 2gb of RAm (almost a must these days), large HDD, and a decent graphics card. I think my only complaint would be the screen resolution, but that's mostly a personal choice. Just remember to factor shipping and Windows XP (~$100) into your cost to make sure you don't go over.
 
Yes, the T7300, T7500 and T7700 all use the latest 965PM compared to the T7200, T7400 and T7600 which used the 945PM. The T7odds actually use a different socket(socket P) than the T7evens(socket M), too.I'm pretty sure that the P965 can actually support the new mobile processors that Intel has coming out later next year, don't hold me to that though.