Thats what I was thinking, quick search got me this German shop: https://www.rohrverbindershop.de/rohrverbinder/ https://www.rohrverbindershop.de/rohrverbinder/

Thats what I was thinking, quick search got me this German shop: https://www.rohrverbindershop.de/rohrverbinder/ https://www.rohrverbindershop.de/rohrverbinder/ But seems like there are plenty of options.