I believe you are asking for something different than what other members are referring to. If I’m understanding you correctly, you’re looking for the molded/padded piece of dash covering that fits to the left of where the steering wheel column fits into the dash NOT the cardboard panel that fits under that?
If my assumption is correct, you’re looking for something more difficult to source. The actual part is NLA. That being the case, you’ll need to look at the secondary market. Although eBay has had them, have you asked Nelson at Vintage Euro? He carries some used dash pieces or may be able to source it for you.
It will be covered in the same MBTex or leather that the rest of your dash is covered. I’d opt to get a pad covered in any color you can find and then recover it in material matching the rest of your dash. If it’s black, that’s an easy do. If it’s something more exotic, maybe more searching on your part.
Please let me know if I’ve understood your request or not.