The parameters in question were for a series of links to affiliate websites. In a pinch, we could switch to using the built-in interwiki syntax, but in doing so we lose some of the benefits of that plugin (specifically, it used to be we could have a single line item in each page with all the parameters, rather than spelling out each link with all associated formatting).
I am aware of the include plugin, but because it won't parse parameters, it won't do the job that is needed here.