A new fan is cheap: $20 at most, plus labor.
But if your system has burnt out its CPU for lack of adequate ventilation and cooling, then the parts to replace would cost about $300 or more, I would guess.
If you have MS Office install media, or a downloaded install file for MS Office, then that might be transferable - though I am not sanguine, since I know how utterly retentive of their property Microsoft tends to be.
Send a pic of the open case by all means, it might help me advise you even better than I have, and it would be a pleasure. Posting on http://www.wikisend.com
would be best, possibly, because our online image posting facility is not always working. WikiSend is drawback-free, reliable, easy to use, and does not require registration.
(-Be sure to copy the WikiSend file posting URL and include it in your reply, of course.)