i can see you have limited your budget even more now. but for that i think your setup looks just fine.
i will just make sure you understand that your CPU can not be overclocked. at this time there is no sandy bridge I3 processor that can be overclocked.
also about that GTX 550TI: for not much more money yo can get a 560 (non TI). it is like an overclocked 460 with better power management. and it can be overclocked to a 560 TI. (and depending on what 560 you are getting you can actually pass it)
it does not cost much more and i will definitely recommend make room in your budget to get that insted.
i found a review that should make my point clear: NVIDIA GeForce GTX 560 1GB Review
it should be only 25 Euro more for a gtx 560 (non ti).