IKEA Vilmar Chair Plastic Connectors Prone to Breakage and Expensive Replacements

The plastic connectors on my IKEA Vilmar chairs broke after only 2-3 years because they deteriorated. I have four chairs. You can only find these parts at IKEA. According to IKEA, they don't have these parts available. However, they are offering a new product at a discounted price of 40% off for the spare parts. They want 250 TL for just one chair that comes with four plastic connectors. The products are made so badly that they break after 2-3 years because of aging. You can't find spare parts for them, and they charge ridiculously high prices for the parts. I want these parts to be available and affordable.