Wrong gun

So, I fucked up pretty good. Ordered myself a 6.5 inch mk4 dissent in .300 blackout. Only problem was that I didn't read what I selected carefully and chose the wrong caliber 🙃 so now I've got a 6.5 inch dissent in 5.56, is there any way I can get the .300 blackout variant now that I own this one? Thanks