A HEFTY LARGE POTTERY PLATE - NZ MADE?

I was at my local Salvation Army store last week..............saw this and at the time I thought hmmm 'no'.  Today I went back to the same store and it was still there so I purchased it.............I don't know who the potter is but if anyone can shed light on its provenance it would be greatly appreciated Also............I'm not sure but in two of the photos there is a possible makers mark..............either that or I've been looking at the base far two long  

I think those markings are just some grit (grog) caught on the base rim.

Ah..............what would I do without your wisdom!  Thanks Ev