Intake manifold leak on an '83 deville hearse

So, I honestly don't know that much about cars or engines or whatever, but I don't like to believe that some ridiculous $$ amounts quoted by mechanics are always correct. I apologize in advance for how uninformed my terminology or questions are, but please bare with me.

This problem just sprung up randomly the other day. My coolant temperature light came on & steam was coming out from my hood. Upon further inspection, I found that it was coming out from back under where I put the oil in. I just had it looked at by some people at a shop that I usually take it to, and they said that after a pressure test they found that I had a leak in my intake manifold. Now, I did notice a teeny bit of coolant under my car, and if my understanding is correct then that's a big possibility. The quote, however, on how much it would cost for the 6 hours of work to replace/fix the gasket was $960.

Any suggestions or information that could help me right now would be very appreciated! I don't have that much money to spend on my car, sadly.