The fateful day has finally come when I must decide whether to repair my 190E 2.3 (156K miles) or replace it.

It is suffering from massive blowby, and I'm told needs to be bored. I don't know what the condition of the head is, but the machine shop seems to think that "reconditioning" it should run around $200-$300. They also think that the work on the block should be around $300. The mechanic who is now in possession of the car expects, at first glance, that the job will run around $1500. I suspect he is conservative, because a piston kit appears to cost about $400, bringing the total so far to $1000 without labor.

The car also needs a new HVAC fan control switch, which I can do myself and a few other odds and ends, but the chassis appears to be generally sound.

I would truly value the input of people who are more familiar with these cars than I am.

Do these costs sound realistic?
What are your feelings about repairing this car or replacing it?