That should do it. However, look at a 1HP or even a 1.5HP sprinkler SS booster pump in 1". it will do far better than the small belt drive feed pump Ray uses.
On my 250 I can run using his feed pump but I almost always use an electric 1" sprinkler pump and that increases to total flow some. My feed pressure using that is about 75 psi, without it I get about 25-30 psi feed pressure. This is what I use https://www.homedepot.com/p/Wayne-1-...S100/203448494. check around, you might find a better price. I got mine thru Northern tool on sale.
Just use that without any belt feed pump, then to your hp pump. It will give you a slight increase in gpm thru the membrane, but likely not enough to eliminate the need for a larger HP pump. My 250 has a 2hp motor and my HP pump, open discharge moves about 5.5 gpm.
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.