The provisions of Articles VII through XIV governing open and selective tendering procedures need not apply in the following conditions, provided that limited tendering is not used with a view to avoiding maximum possible competition or in a manner which would constitute a means of discrimination among suppliers of other Parties or protection to domestic producers or suppliers: ... for additional deliveries by the original supplier which are intended either as parts replacement for existing supplies, or installations, or as the extension of existing supplies, services, or installations where a change of supplier would compel the entity to procure equipment or services not meeting requirements of interchangeability with already existing equipment or services.
