From my experience, there are two basic features of a system to consider. Does the unit need to have it's own reservoir tank or not? How many ports do you need?
MP Systems pumps offer both types (reservoir/non-reservoir) with a variety of port configurations. Mike Sayers, the founder of the company, really knows the business of high-pressure coolant pumps. I am trying to find contact information on his company, but all I've found so far is his biggest distributor, MonsterSwiss.com.
How many gallons per minute would you need at 1000psi? What machines are they going on? How big are the coolant tanks on the machines, and what coolant or oil do you wish to run?
There are many factors to consider in choosing the best system, these are most of them.