IKEA should make it easy to buy replacement parts for their furniture. Currently even for models still in sale it is usually impossible to get parts. You can go to an IKEA store 'used' section, if they happen to have this model returned by some customer, they will sell you parts, but most likely you will return empty-handed.
Recycling large furniture, such as sofas, just because they have one tiny part responsible for folding broken, is not really an eco friendly way to go.