There has been a number of discussions around this on the forum. From what I gathered, nobody knows for sure. There was a print run of shadowless cards, that were later stamped as ‘1st edition’ and I believe it was 6 or 7 more print runs of unlimited cards.
www.elitefourum.com/t/an-elaborate-attempt-at-print-run-estimation-wip-5-8-18/20273/1
www.elitefourum.com/t/shadowless-vs-base-1st-ed-population/25095/1