I use this one and it works fine.
Super repairman 7 Pin Round to 4 Pin 5 Pin Flat Blade Trailer RV Boat Adapter Plug
https://www.amazon.com/dp/B07RG41RTQ?psc=1&ref=ppx_yo2ov_dt_b_product_details
Note that it can be a pain to remove due to the Tesla plastic cover but it's not a big deal.