If this is your first rodeo with portablizing, I would highly advise against using PTH regs or a PSU for a portable, you'll need an additional lithium charging / protection circuit, and the overall wiring is going to be a lot more complicated. There's a new prototype of the PMS Lite that's currently undergoing testing, once the boys over at 4Layer deem it good, it'll be back in stock (hopefully soon). So, if you want to make a portable, I would highly advise waiting a bit longer for the PMS to come back in stock.
On another note, if you want to dip your toes into portablizing without the expense of a portable, I would highly recommend starting with something like the
Noldendo Miicro. It's much easier to build, and a lot cheaper than a portable. You can either use PTH regs or a PSU for that build. As modio posted above, I am selling some premade PSUs if you'd be interested in going this route!