I know this is a long shot, but I will try. Four years ago, I bought this Alabama-D state quarter coin and die set off of eBay. It has a box, quarter, die and COA. A couple months ago, I noticed that the COA SN 2209327 did not match the die SN D3-200510. I looked at the COA and saw that it is for a Mississippi-D die. If you have the Mississippi coin and die set D2-209327, I have your COA and hopefully, you have my 3200510. Thanks
The dies aren't all that impressive since they grind the entire die face off. The 1996 Olyimpic dies are the impressive ones.
Conder101 is right, the Olympic ones are far superior, you have a fair amount of detail remaining. The state quarter ones are ground smooth, you don't know if you have the obverse or reverse die. In 1998, I think the mint offered dies for pennies, nickels, dime sand quarters, packed it with a COA and a coin in a pouch, all in a USPS box packed with foam. In 1999, they did just the state quarters. After 1999, they put them in nice packaging.
maybe try contacting the ebay seller first, see if it was his mixup and he maybe has the other set? Long shot of course, but this might be the easiest solution other than seaching the world basically blind hoping someone sees your post that just so happens to have it. That's worth a shot too, but always best to retrace your steps. Ebay seller might even know if they had the other set and who they sold it to. I don't think this is a mint mix up, I think it's a 3rd party mixup by someone that had the sets together at one time and didn't pay attention to cert and die numbers.
I think you are right that it is not a mint mix up, the dies are a year apart. The problem is that after four years, I am not sure whom the seller was. Purchase history on eBay only goes back two years. I did contact the most likely seller and I will see how that goes.