Buying Short Block

Thanks for all ideas and feedback.
Sorry for upside down pictures
I Picked up the block today for (4.25 bills)
It's a standard bore
Block number 4323330318-2 Date code 84
Crank number 4751841 (cast or steel) - Could it be 340 Crank?

Inspected
-No rust in any of the lifter hole or anywhere that's critical
-Crank turn freely.
-Cylinder wall look good.

By the Way.
What Harmonic balance I will need for this block? Would any 318 internal harmonic will do?
http://www.summitracing.com/parts/sum-163273/overview/year/1973/make/plymouth/model/scamp


The tag has a serial number that I need to call Detroit Michigan to get what has put in the block.
Scamp