I would get one of those bikes used.
You can find a used trek 1500 (the name changed to 1.5 back in 2006 I think) for about $400 bucks.
9 speed with a mix of ultegra and 105 in some instances.
If you live in the NYC area, I have a trek 1500 discovery channel team edition 9 speed, with all 105. Make me an offer.