This reminds me that I just repaired my old Eastern bloc made speakers, a pair of Videoton DCR 2520A. The woofers have out-of-spec surrounds now since the now for real co-op (?) that bought the tools from Videoton during the robber-privatization worn out the tool needed to make the up-to-spec surrounds. They still had the tooling for the midrange speakers, and after some modification I could use some general purpose surrounds from Aliexpress.