In Sales / Warranties could you activate the SO Number so you can click into that Sales Order? This feature already exists in Inventory / All Products / Movements so should be fairly straight forward one I would have thought.
Perhaps a bit more detail on this screen (product name, supplier & sku) would also be beneficial? Ideally the warrantees should be linked to the Purchase as well.
Maybe go one step further and have a "report a warranty issue" to the supplier feature? (creates an email template)