honestly, if you're going to build a stroked 318, I'd start with an '85-91 block. they have factory roller cams, 302 heads. the roller cam is the biggie. you can get it reground, or get a roller cam and reuse the stock roller lifters at a much lower cost than the retrofit roller lifters.
putting a stroker crank in requires at a minimum new crank, pistons, and block clearancing if using stock rods, IIRC.
any 318's stock heads will be way undersized as far as flow to have any power above about 4k RPM
