If it's all downhill, there are at least 3 maybe more options.
To remain pumpless, you could extend each of the 3/16 lines to the destination, likely fewest issues. Choice 2, run all of the 3/16 into a 1/2" mainline, avoid dips, gravity will carry it to the destination, no pump. Or run all into a manifold and run a battery powered (12V) diaphragm pump. I suggest you price all 3 choices and then decide. You may need to extend the 3/16 to the manifold and pump location because of the limited choices for fittings into a 1/2" mainline if going that route, or likely a diaphragm pump on a battery can handle it all.
Dave Klish, I recently ordered a 2x6 wood fired evaporator from A&A Sheet Metal which I will be converting to oil fired
Now have solar, 2x6 finish pan, 5 bank 7x7 filter press, large water jacketed bottler, and tankless water heater.
Recently bought another Gingerich RO, this one was a 125, but a second membrane was added thus is a 250, like I had.
After running a 2x3, a 2x6, 3x8 tapping from 79 taps up to 1320 all woodfired, now I'm going to a 2x6 oil fired and a 200-425 taps.