There is basically nothing super special about the heavy vinyl mats. For ACC it is still the same mold and process, just a different material. Basically no different than ordering the Essex material or Cut Pile vs the standard 80/20 loop.
For us, if I get my order into ACC before 3:00 PM, it is cut, molded, packed and shipped basically within a a 24 hour period. We have a very good relationship with ACC and they work very well with us. Our account rep has over 10 classic Mopars and the the VP of Sales has been involved with the Mopars for many years.
The reason that ACC does not list the vinyl mats is that they are a tiny fraction of the sales for them. Although we relate ACC as a vendor dedicated to the carpet and trunk mats for our old cars, the old car market is not their bread and butter market. They rely on the late model car market to pay the bills and the carpet for the classic cars is supplemental income.