Silver red sea max 130 mods/parts?

[thehobdenmarina]

Hey guys I recently picked up a old display rsm130 from my lfs. The tank is actually brand new never set up but being a display it doesn't have any pumps or plumbing.  It did come with the skimmer but again no pumps. I'll post some pics, but what I'm looking for is 2 returns for the return outlets and a way to run them off my jebao pump.  Are these fittings easy to find or do I need to buy the actual parts? The holes are about 9/16" or so. I'm not sure what to use. Plus parts are hard to come by for it. Any tips would be greatly appreciated 

 

Here's the holes I'm talking about. Is there a generic return nozzle I could use with and elbow on the back side?

 

And the jebao pump that I have which fits perfectly and moves a good bit of water