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The only one I see with cup holders is a "representative photo" from a different vehicle? Looks like only the two top photos under "Step 1" are from a Model S.
www.eveverything.com, has both covered and non-covered models, that I have found to work fantastic. The Raw Sport is the Foam Model. I had the Insane Model, but sold it here on the classifieds, and got a Ludicrous with Dual USB ports. btw, they are fast charging ports, unlike the ones in your Tesla upfront.
If you are looking for inexpensive, www.evampedup.com has some scratch and dent sales from time to time. A buddy picked up a black leather one for under $250. You have to watch for them to show up.
Not sure if this will do, but it has worked well for the kids in my Model S. Has 2 cup holders, and storage for other items. Got it at Wal-Mart for about $10.