It is not from an "orange-brown" plate or an "inner line" plate, so must be from plate 4,6,7 or 8: Scott #11. Most of the frame lines are missing, so probably can't be plated. It doesn't have the typical top label recut of plate 4, so I'd guess plate 6, 7 or maybe 8, all of which exist in that color.
There is essentially zero chance that the stamp is a Scott #10. If I were going to try to plate the stamp, which I am not going to do, I would start at Plate 8, then go through Plates 6 & 7. I do think there is a chance the stamp can be plated. It is highly likely that the stamp was printed in the second half of 1856 in a '56 brownish carmine. The color is slightly darkened by atmospheric pollutants.