The Reserve card has a 10K MQM/40K miles offer after first $3K spend. Presumably, OP has not had this card before (otherwise would be ineligible for bonus). If OP means end of this month (tomorrow), I would not expect card to be available by then. If OP means end of Dec, it's a bit risky as the MQM bonus might post in January. Unlike the annual spend MQM boosts, I don't believe they backdate the sign-up bonus MQM's just because spend was in previous year. If OP has DL Plat Amex, there's a 5K MQM bonus for upgrading it to a Reserve card which I believe posts immediately (I did the upgrade a few years ago).
Yep, there is is right on Delta's site. I checked the AmEx site and didn't see that offer, but it seems it won't show me that offer because it "knows" that I have that card already, even if I'm not logged in to my account.