For fans of retro Americana, an Etsy seller going by the name of lacklustreco has a good stock of Vintage Gas Station Numbers available to buy.
They have a variety of numbers in various sizes; medium measuring 12 inches tall by 7.5 inches wide, large 20 by 12.75 and the enormous XL size 30 by 16. The exact age of the signs isn’t given, but they are vintage so have various degree of weathering that adds to their character.
They are priced $16, $26 and $52, although adding shipping costs will inevitably push the price up especially to send them anywhere outside of the USA. Buy them from Etsy.