PSA (or other) uncatalogued card grading - question

[Frankish]

Has anyone had luck getting PSA (or another grading company) to grade cards not in their pop report/catalog? What is the process? Do you just send it in and then the grader refers it to their research department? Or do you contact the research department directly and hammer it out before submitting? Normally, I'd just start with the last but with all the delays these days I figured getting a response might take forever.

I've actually ended up with quite a few cards that fall into this no-mans-land. Generally, I'm content to just keep them in binders. There is a Monty Gum team card for Ajax 1964, though, that I'd really like to get graded, as it would be Johan Cruyff's first card.

Any advice is greatly appreciated. Thanks!