A good used Jaguar 420 air intake, it's in good condition and has had a sympathetic cosmetic polish, there are still some age related marks (patina) on the surface (see pictures) but will still look good under the bonnet of your classic.

If you want a concourse mirror finish this will need further work.

This has the larger 2" ports for the HD8 carbs so if you're planning to upgrade your XK engine to 2 inch carbs you'll probably need one of these.

Jaguar part number C26961 and again it will only fit HD or HS8 carbs