What monitor are you going to run it with?
SCS 700, 750, & 760's are very limited supply and if you have trouble with them there's almost no repair!
The parts for the pumps like you have in the picture are very limited.

We have a few of the newer style direct drive injection pumps on hand (reconditioned and tested). 
You would need a motor control like the one that's inside the box in your picture.

Kevin @ L&D