How can you manage spelling substitution for a multinational website?

Consider a website that allows you to pick your world region, say UK and US. Pages include:

• Global content - the page content is the same in all regions, therefore there is one version of the page (e.g. About us page)
• Region varied content - the same page exists in all regions but the copy for each region differs (e.g. Customer support page)
• Region only content - the page only exists in one region (e.g. apples are sold in UK and oranges are sold in US)

What is the most efficient and expedient way to handle spelling differences? In UK we spell colour, in US we spell color. How can this be achieved without have to duplicate common content simply to cahngespelling.