I wasn't able to find a scan of both colors, so here's the best I can do -- a side-by-side comparison of swatches from the Michel color guide. Interestingly enough, the Michel color guide doesn't list schwarzolivgrün (black olive green), so I went with the nearest color, schwärzlicholivgrün (blackish olive green). Not sure how much good it'll do you due to variations in monitors, scanners, etc., but it's worth a shot.
