Assuming you had none of the NAOMI2 hardware you'd need
N2 Mobo $500
GDROM and DIMM board with cables $300
Those prices are approximate. Keep in mind that with this hardware you can play a ton of other great arcade games that are still making money in the arcades.
Here's a
listIf anyone is interested in the hardware I can put you in touch with reputible sources.
-Goz