This one from Camping World works great and is on sale for a heck of a lot less than I paid for it: Adjustable Water Regulator - Lead Free - Valterra A01-1117VP - Faucets & Inlets - Camping World
And it includes a gage and all of the extra brass adaptors that may not be included with the one from HD (if you can find it).
If only the kitchen lacks flow, I would look for a restriction in the pipe, fittings or valve somewhere near the kitchen. I have seen the shut off valve clogged with debris left from the plumber not flushing the lines first.
Ole and Anne Anderson, Highland, Michigan
'02 Adventurer 32V, Ford F-53, ours since 4/08,Hankooks, Konis, SeeLevel, CHF
'84 CJ-7 , 5.3 Chevy, 3" lift, 33's, Detroit Locker, Fiberglas tub, winch, hi-lift