I would budget between 1400 and 2500 for a complete engine if the heads can be reused.
I just did a 318 a year ago and it cost me around 2500 total which included a 0.020" overbore, 10/10 on the crank, balance, a new Racer Brown Cam and lifters, a complete set of heads from a reman shop, and long block assembly including the intake. All in all not bad.