Armstrong no longer makes them
Armstrong's site says Grenoble or Wellington are "similar", but I don't see a close match. So, stop looking, you won't find it, unless someone's throwing out theirs. Rip it all down and put up plain-flat-smooth or re-use your 30's as a border, center accent or checkerboard. Sorry but, gone is gone and none have come back into production yet by any manufacturer, as far as I've seen.
What did you end up doing? We have the same issue and are looking for solutions.