Is my six-year old touring bike worth repairing?
As LBS mechanic, I also would recommend to repair - the cost is sufficient. Your bike will be almost as new.
So if it's a bike that worth repair (like mikes mentioned), and your tires and derailleurs are in good condition yet, go for it.
If you know that you should replace tires or derailleurs soon, better is to buy a new one with all parts new and a warranty.  

Edit: if you will anyway buy a new bike soon, you should consider whether you want to do all this repair, or a part of it will be enough.