Prezzo is a restaurant chain, and the availability of products they use, such as Calabrese ketchup, can vary by location and time.
Regarding Calabrese ketchup, it might be a proprietary or custom product specifically made for Prezzo, or it could be sourced from a specific supplier. Unfortunately, without up-to-date information, I cannot confirm whether it is available for retail purchase or provide a direct link to buy it.
To find out if Calabrese ketchup is available for retail purchase, I recommend checking Prezzo's official website, contacting them directly, or visiting their restaurants to inquire about the product's availability and potential retail options.
If Calabrese ketchup is not available for retail purchase or you can't find it, you can consider exploring other gourmet or specialty ketchup brands that may offer similar flavors or ingredients. Local gourmet food stores, specialty grocery stores, or online retailers could be good places to look for unique ketchup options. Just search for "gourmet ketchup" or "specialty ketchup" online, and you should find several options to choose from.