Where can I get a new gas metre box?

Does anyone know how I can get a replacement gas metre box for the front of my (new) house please? The current one is missing its door and my metre is exposed. Do the gas suppliers sell them and will they fit them for customers? I am NOT good at DIY! Thanks in advance.

Complete boxes and replacement doors are widely available at builders merchants, plumbing suppliers etc. You can even get them on Amazon. A plumber, electrician, carpenter or any reasonably handy person could replace or repair it for you. Fitting an overbox is another possibility: https://repairmymeterbox.com/product-category/plastic-overboxes/