my head amp has recently been upgraded,its miles better than the standard ha-500. i bought it to run a denon 103sa which it kinda was designed for. since then i now use an audio technica art-7 cartridge and the ha-500 also works well with it too.
as regards to what mc i would recommend? well thats a tough question to answer,depends on your budget,your arm for matching etc plus i can only really talk about what ive owned which isnt a great deal of mc experience.
hope that helps.
if you arm will cope with it,a denon 103r would be a great choice for dipping you toe in,but without knowing the effective mass of the pa-1000 its hard to say. if its 16 grams or over it will be fine