Is there a keyboard case made of a model # A1584?

Very few, if any.

You have the same iPad Pro year and model as mine.

These iPads are almost 6-years old, now.

Look to Amazon. There are a few third party keyboard cases still available.

I am not a search engine.

Best of Luck to You!

In addition, you can always use a separate external, wireless Bluetooth keyboard or wired keyboard with that iPad using a Lightning to USB adapter.

Plenty of separate, wireless Bluetooth keyboards available to use with that older iPad Pro.

Good Luck!