IKEA PAX Series Attachments

Help! We have shockingly discovered that Ikea has discontinued the 70 cm high tops for the Pax series, at least in Germany. What are old building residents supposed to do now? That's such a waste of space! I'm not keen on putting boxes on top; that just collects dust.

Does anyone have an idea how to make an extension themselves (simply buy a tall carcass and split it in two? Does that look good? Is it stable?)?

Or does anyone know if these tops are still available in other countries (is there IKEA in Poland?) and if so, in which ones?

(I hope this isn't old news in this forum, but I couldn't find anything on this topic using the search)

Thanks in advance for any replies,
lyra

So: the inserts have been removed everywhere. As a replacement, you can use, for example, kitchen base cabinets, which you turn upside down and then place on top. You just have to see which doors you choose.