These items come up for bid every so often. For around $10 you can purchase this postcard which depicts Levi Miller. Here is the seller's description:
Up for auction is a postcard featuring Levi Miller, an African American / Black Confederate soldier, 1910s era. This is an unusual card, as the caption reads: "Levi Miller, Only Colored Confederate", but there numerous other African Americans who battled for the Confederacy. The card was mailed in Sadler NC by V. McGhinnis (sp?) to Minnie Oxford in Taylorsville NC in 1910. One of the messages notes "cousin Levi age 62 (or 67)" (see 3rd photo). In good condition, a few minor corner creases, light little spots and rubs / scrapes on some edges, but the image of Levi is clear…obviously a photo taken in the 1900s when Levi was older. I believe Levi was a nurse/caretaker for a Confederate officer, officially inducted into his Regiment in the field for some heroics during battle. Buyer pays $1.05 shipping and handling in the US.
But don't let the author's description keep you from engaging in wild speculation. I am told that Miller was present with the Texas brigade at both the Wilderness and Spotsylvania and received a pension from Virginia. This should be sufficient evidence for most people to weave together a narrative that satisfies their deepest needs in Confederate lore.