The procurement of infrastructure systems by the public sector is very costly, long and not transparent since the processes are based on preparing huge amounts of documents which are difficult to be kept consistent and to be used (e.g. bid evaluation). Acquisition architecture frameworks (AF) are metamodels, developed to model the whole enterprise/system life cycle stages including system procurement. Our previous study analyzed the currently used AFs such as DoDAF, MoDAF and TRAK to assess their adequacy and efficiency in modelling the infrastructure projects. The results showed that many of the procurement related concerns are overlooked such as financial matters e.g. cost and revenue calculation; and risk management aspects e.g. risk calculation and risk allocation. This paper focuses on identifying the procurement concerns and adding new viewpoints to the architecture frameworks; and developing a domain specific language based on SysML to model the new viewpoints. A methodology is provided which shows how the metamodel (abstract syntax) and the language stereotypes (concrete syntax) are developed. The results firstly show the 18 identified viewpoints of procurement domain and then one of them (project funding) is chosen to be described in this paper. The conceptual definition of the 'project funding' viewpoint and the models it generates are illustrated as example diagrams of this DSL. This DSL can be used by the domain practitioners, who are the contracting officers and procurement managers, to generate the contracting materials to facilitate the contracting process, assure the consistency of the procurement documents, giving better project outcomes.