Shopify:
Navigate to Searchanise admin panel → Instant Search Widget → Content and check the Show compare at price box.
Magento:
Navigate to Searchanise admin panel → Instant Search Widget → Content and check the Show original price box.
Available starting from version 3.1.3
CS-Cart:
Navigate to Searchanise admin panel → Instant Search Widget → Content and check the Show list price box.
Available starting from version 3.3.10
Please don’t forget to save the settings by clicking Apply Changes!