It's not about the new foam, really, but about the imprints in an old one, so that I'll know the safe arrangement of parts in the case. Upholstery folks have plenty of different foams here, there is at least one workshop in every town, and it's not an issue to buy a piece this way or another.
Do you remember if there were light-tightness issues with your model? The ceiling is illuminated quite brightly with what I have, so maybe instead of tinkering, I should look for a model with the head, that yours come with and just get rid of mine?
Thanks for the replies