It doesn't really matter in the AGA range of Amigas as they can easily be switched to NTSC or PAL compatibility mode through kickstart early boot menu, and since you have an Amiga monitor, the 50/60Hz - PAL60-NTSC50 - PAL/NTSC combos that would come out of the RGB port are all displayed well and tolerated perfectly.
Now, if you plan to strictly use a TV, then you'd need a good multisystem one in order to properly tolerate the above mentioned potential funky modes.
Pre-kickstart 3.0 Amigas do not have the built-in PAL/NTSC software switch in the rom, thus if not upgraded to 3.1 kickstart, cannot run nicely in any mode other than native (PAL or NTSC). There are of course hacks out there that go around this, but they are not newbie friendly.
My advice? Plan to play a lot of games? Get a PAL A1200 and run anything you'd possibly want with your 1084s monitor. Compatibility guaranteed, almost always, as majority of good stuff out there is PAL specific. Just one of the reasons why almost every Amiga that I own is a true PAL unit, even though I live in Canada (NTSC land). :-)
The only extra that you will need is a 110V Amiga 500/600/1200 power supply which you can easily find.
