They are not currently available anywhere that I know of.
There was one small garage company that made all the van dividers. They were sold by Interlink Supply, by American Van and several other companies. He retired and no more were being made.
A former Interlink Supply employee started a sewing company called Custom Bags that began making the van dividers in what was the most popular size at that time. Making a quality pattern for the fabric and where all the snaps goes has a start-up cost for each model. Right now, our product managers do not see enough sales to justify the investment in new patterns for the larger taller vans. I keep suggesting it. They want to be sure we would sell at least 100 a year to get back the initial investment.
If enough people wanted to order, I could get them. Similar to the ones we do sell for the older style vans but a perfect fit for Transit or whatever other van it was made for. If you want one for Transit, let me know. More names of potential customers would give me some ammunition when I go back and prose the additional sizes again.