Reddit mentions of 3-Pole Flush Mount Industrial Grade Range Receptacle, Straight Blade, Black, Nema 14-50R, 125/250 Volts, 50 Amps

I would be happy with a 240V 50A NEMA 14-50

Yea, that won't work. You are trying to plug a 14-30P into a 14-50R.

The plug is a 50 amp unit, and the wall socket is rated at 30/50.

https://www.amazon.com/Leviton-279-Receptacle-Industrial-Grounding/dp/B00009W3AA

https://www.generatorjoe.net/html/web/outlet/nemaspecs.gif

With respect I asked you to show me how these were certified as you claim. You did nothing of the sort. The best you showed is that these have special nylon bodies to prevent breakage of the plug body itself which says nothing about the quality of the wiring or it's ability to prevent fire or wiring disasters. Take a look at this:

Leviton listed as industrial for $8.65
Leviton Specs

Nylon body, Industrial Grade, 10 year warranty

You exactly proved my point. People take something out of context (in this case the example part number Tesla uses in their documentation) , start circulating it as "fact" on the internet then justify paying far more than they need then needlessly argue the point without any real data scaring people away from useful solutions. =(

NEMA 14-50 is one type of plug commonly used for EV's, rated up to 50 amps. Looks like this:

https://www.amazon.com/Leviton-279-Receptacle-Industrial-Grounding/dp/B00009W3AA/ref=asc_df_B00009W3AA/?tag=hyprod-20&linkCode=df0&hvadid=198089608681&hvpos=1o2&hvnetw=g&hvrand=16570288418637110563&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9032168&hvtargid=pla-357917644205&psc=1

There are other 240 V plug types too. For example, here's a 30-amp rated variety:

https://www.lowes.com/pd/Utilitech-30-Amp-125-250-Volt-Black-Indoor-Round-Wall-Dryer-Power-Outlet/3775477?cm_mmc=SCE_PLA-_-RoughPlumbingElectrical-_-WiringDevices-_-3775477:Utilitech&CAWELAID=&kpid=3775477&CAGPSPN=pla&store_code=2842&k_clickID=1738a1cb-ecda-4ae2-ab8c-92e4d9e66678&gclid=CjwKCAjw0oveBRAmEiwAzf6_rMEamS_g0FUQVn0Ab7_8o_9ioCAqVKn0_PeesKxkZNWaTW5bjbFJzhoCAUoQAvD_BwE

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You'll definitely need to lug the cable around in your car, unless you can leave it at work. But as \u\ChalupaCabre mentioned, there are some fairly cheap ones you can buy, such that you'll have two.

You can always just install a new outlet yourself. Go turn it off at the breaker, disconnect the old outlet, install a nice new NEMA 14-50R. You can check the breaker to see what the amperes are and down regulate your car to match that. You could have an electrician come out and update your break if it isn't 50+ amps, or you could do that yourself after flipping the mains switch.

All up to you and your comfort level with electricity. Just know, don't play games with it. Either be confident based on sound knowledge or let someone else handle it.

EDIT: This is what I installed in my garage: https://www.amazon.com/Leviton-279-Receptacle-Industrial-Grounding/dp/B00009W3AA