Oh man you REALLY need to get something besides stock fan that has a higher RPM and more CFM for air movement, the tornados are the best but are LOUD as all hell, and without a fan controller they are almost unbearable as I rarely ever have mine on full blast...
I would say do some research on what the 'average' normal temperature of that particular processor should be. As I don't know too much about Intel, the only thing I do know is that they run cooler than AMD's and when OC'ing I don't like my AMD do be in the 50's so with that in mind it seems like your Temps are pretty dern high...
Honestly man I really wouldn't push it further because your temps will definitely hit up in the 60's until you get a better heatsink and fan, and some Arctic Silver to put under it.
BTW: When you say stable...how long did you rune prime95 to come to the conclusion it was stable. They say minimum 6 hours, but I'm not satisfied with my computer unless it hits atleast 12+