You can find Campy chains for a lot less than that. https://www.ribblecycles.co.uk/campa...ain/#pid=29354

If you've ridden Campy chains for 25 years, like I have, you might find that a Campy chain will show almost no measureable elongation over a 12 inch length, even after 5,000 miles. That doesn't mean that the chain is still useable. There's more to wear than just elongation measurement. At that point, you can measure the space between the rollers and find that they are severely worn and the side clearance is at least twice that of a new chain. I use a 6mm wide plug gage to evaluate roller wear. If it will slide between the rollers, the chain is shot, regardless of the elongation.

What you don't want to do is use only one chain for that long. If you do, a second new chain will skip, even though it was changed with little elongation. Use three chains is a regular rotation and the cassette will easily last as long as all of the chains, with no skipping. I rotate every time I remove a chain for cleaning.