Simplex 4004 Annunciator Driver Card?

I’ve been scouting around for one of these for a long time. I know there is/was an annunciator compatible with these panels and those are I believe the little ones Space Age Electronics made/makes for Simplex, or are they the 4606 series annunciators? And how rare are these cards that drive the annunciators? I’ve been scouting around for one for a long time but have never come up with any evidence that they were made for long or how rare these are. I’m assuming due to the lack of information they were pretty rare. Or perhaps only for custom jobs? Reason I ask is because maybe down the road sometime next year I want to add an annunciator to the system but I know I need that card in order to even program it to work let alone what annunciator they were compatible with, as the manual doesn’t state specifically. The card has a part number too but I can’t think of it at the moment and I’m typing this out on my phone and don’t have the manual file saved on here; it’s on my MacBook which I’m too lazy to go upstairs and turn on.

Of course this is just an idea; it’s not like I really need an annunciator because of the size of my system, but at the same time it would be really cool…although it’d have to be next year because who knows how expensive that card is…and it probably wouldn’t be cheap by any means. Just looking for some info.