Have you looked into buying the hardwired version and adding your own plug to it by using a 14-50 cord like this one at Home Depot for $20. Use only the black and red wires for L1 and L2 and use green wire for ground. Disregard the white wire. (Electricians on TMC, please correct me if inaccurate).
You can then buy a Referral award Elon Signature HPWC from a willing seller for ~$400 or even less sometimes. Wire this cord to the Elon Signature HPWC and you've got yourself a $420 HPWC.
You may then consider taking your Tesla HPWC private as long as funding is secured.
Trying to buy from Tesla will be $500+sales tax.