Was that discontinued? I don't see it anymore on their site.
Did you man NEMA 14-50?
It does look like they discontinued HPWC with NEMA 14-50 connector. I suspect they sold very few of these. No reason you can't buy an HPWC and a 1 foot NEMA 14-50 pigtail and attach it.
It may be they sell this instead: https://shop.tesla.com/product/corded-mobile-connector. Not quite the same, but does the job. Not any faster with the HPWC.