There's one on eBay now
NEO GEO MVS NIGHTMARE IN THE DARK WITH VERY LOW SERIAL 000215 \\FREE SHIPPING//
NEO GEO MVS NIGHTMARE IN THE DARK WITH VERY LOW SERIAL 000215 \\FREE SHIPPING// in Collectibles, Arcade, Jukeboxes & Pinball, Arcade Gaming, Replacement Parts | eBaywww.ebay.com
I know the price(s) is sky high but like a few MVS carts out there, it's one of few titles you'll hardly see any popping up for sale at any price point. Pochi and Nyaa will be another example.