Parts for Grönlid

So i bought a small gronlid sofa at Ikea a few years ago and now I'm moving. i wanted to buy a second armrest (i only have one because i did not have enough space for 2) and another seat so more people could sit on the couch comfortably. Now I saw that the Gronlid Series was discontinued in 2024 and I was wondering if anybody knew if I could by parts of another series that would work with Gronlid. Because I really don't want to buy another couch, that's way too expensive for me. I would be so grateful for some tips.