However, it turns out that there are regulatory roadblocks to Tesla Motors selling an EV power cable with a 240V/50A connector. Basically, it's illegal.
The existing EV owner community knows that the best way to charge their car on the road is to find an RV park and use one of their 240V/50A plugs, so obviously RVs have these types of connectors. When we had our RAV4-EV charger installed in our garage, we had the electrician install a 240V/50A outlet and put the corresponding plug on the charger. So, if we ever want to take it on the road, we just unhook the charger from the wall, put it in the back and map out stops at RV parks. No problem.
Unfortunately, there are laws that restrict the types of plugs that EV manufacturers can sell, but these laws don't apply to RVs. Tesla Motors considers it absolutely essential that owners have a way to charge from these 240V/50A sources and will find us a solution, but it's not here yet.