I'm trying to be a bit more organized with this than I was yesterday, so I'm going with more words, fewer pictures:
Every single gold or near-gold that I have may possibly be discontinued: but I think these are possibly still available if you hunt around:
Khroma Fairy Dust - apparently there was a lawsuit and Khroma is now Kardashian Beauty, because of that. You may still be able to find old bottles of Khroma around, though. This is a nice small gold glitter in a clear base. I've ended up using it a lot!
Colorstay Fall Mood, which I bought at Big Lots lately (reads as sort of a rose-gold metallic)
Pahlish Pyrite (still a couple of bottles, at least, available at that link)
China Glaze Mingle with Kringle, from the 2013 holiday collection
SOPI I Only Shop Vintage (check Big Lots for this one too)
Milani Gold Glitz
Really, you see both red-violets and more neutral purples as Mardi Gras purples. I'm not an expert, but I think it's really intended to be a more neutral "royal purple" - but I don't think anybody's going to throw you out of a Mardi Gras party for having a purple that's too red, either. So something like Sinful Colors Fig or Triple Shine Vanity Flare would probably work. I also think SH Royal Invite is a current color - it's more on the blue-violet end, but it reads plenty purple for this purpose.
Other colors that I have that are more what I think of as Royal Purple are:
Here's my purple nail wheel from a couple of months ago:
Some I didn't get around to on yesterday's list:
Illamasqua Viridian - dark and a bit blue-tinged, but much closer to emerald than, say, the Rococo Darkest Emerald is. I'm not sure if it's still "in production" but I know Sephora still had it not long ago
Zoya Veruschka - the Matte Velvet - if you didn't snag it while it was available again last fall, then it's probably not easily obtainable, unless you're willing to try eBay to get it. Gorgeous, though.
China Glaze This is Tree-mendous - another one from last year's holiday collection
Also from holiday collections past: Pahlish Boughs of Holly, Julie G (Gumdrops) Mistletoe
Here's a whole ton of greens that Zoya is still making. And purples. And golds (although some of those are more gold than others). (Zoya's website is so easy to use. And none of these are affiliate links, if you're wondering.)