Gave it my best shot and basically ended up with what Roxas came up with. You're on a budget that really doesn't allow for any flexibility whatsoever - I'd seriously consider just getting a cheap laptop if I were you.
Im doubting the cpu, thats why i went for an apu with 4 cores and a gtx 650ti which is very similar to the 260x in terms of performance. 2 cores are kinda outdated. I know intel has better cores but more cores will be better (and in some games are).