There is more information available, but in German only, here: https://capra.shop/munition.html
If you have a problem with lead bullets, and need lead free, this might be an option. However I don’t really see a huge market for this new caliber.
Regardless, the Internet now has some information written in English about the 10.3 CAPRA.
The price for 10 rounds seems to be 65 Swiss or about the same in USD.
50 bullets, for reloading, is 100 Swiss or 103 USD.
A similar caliber is the RWS 10,3×68 mm Magnum. Check it out here in TFB’s article.