I've got both Pistol Poker and Mystery Castle...pretty sure the MC production number of 500 on ipdb is bogus...the serial numbers collected and statements by Gottlieb put it at 250. Similarly I believe the 250 for PP is wrong too...I've seen way more of them than MC.
With AMH now and RZLE to come I guess I'll have as many rare games as common games...go figure. I like the rarity factor but more so like the games because theyre fun.