The image in the op shows a sword that doesn't look much like a model 1860 officer's sword, maybe an 1850 model? The second sword image is a model 1860 officer's sword. The third sword image shows a fancy cavalry saber hilt, like for an officer's model.
Is his left arm prosthetic? It looks very unnatural. If his hat and one glove are in the other hand, then it's on purpose to show the one resting on the sword hilt.
Is his left arm prosthetic? It looks very unnatural. If his hat and one glove are in the other hand, then it's on purpose to show the one resting on the sword hilt.