Hi Digital3: I don't know what the cost of a rebuild or exchange is for the following reasons: Prices are determined by the distributor in each market rather than Lyra. My strengths are in the field of engineering, not business.
My recommendation is to get in contact with your dealer and have him send it back to the Lyra distributor in your country, or if your dealer is no longer available, feel free to contact the Lyra distributor directly. It always helps us if you could include a short note with the cartridge, clarifying what you want to have done. For example, you could ask us to inspect the stylus, suspension and dampers for wear, and rebuild or exchange the Delos if the wear has proceeded too far; but if the stylus, suspension and dampers still have some life in them, that we clean and adjust the cartridge so that you can get a few more months of usage before actual replacement.
kind regards, jonathan carr