Your best bet for pictures, I think, would be to google search for "2017 Sprinter 353FWDEN for sale".
You'll get several hits. The first will be an RVTrader site with 3 trailers for sale.
https://www.rvtrader.com/Keystone-Sp...3FWDEN%7C68942 There are 16, 18 and 12 photos of each of the units. You might find a useful photo there, or on one of the other google hits.