price for the repair seems right.
Depends on the mileage and the general condition of the car, and what
else you've fixed recently (brakes, tires, water pump, radiator, etc.)
to decide if you do it.
I mean, for $1200 could you get something better that you know wouldn't
break in two months?  Of course not.  Could you get something better for
$5000?  Of course, but that's a lot more money than $1200.

The whole "repair costing more than the value of the car" mindset, I
have always thought, is rather pointless, because, well, you CAN'T
replace the car for the cost of the repair.

You have to ask yourself, "would I pay $1200 for THIS car right now, if
my friend were selling it and I knew he just got all this work done on it?".

Would I?  No.  Grand Ams are too small for me, and I fix things myself.
If I couldn't fix things myself, I think I'd own a new car every four
years.  I say that after dumping $1200 in the last year into my "free"
Buick Regal.  That would have been $4000 if I was paying labor and full
price for parts.  So, that's $4000 for a crappy old beater vs the $4800
I could have made in payments on something brand new.

Hey!  I may have just talked myself into a new car!
lol

GW
1970 Pontiac GTO (the baby)
1991 Buick Regal (the beater)
2002 Chevrolet Blazer (the Blazer)