Open source system level simulators play a crucial role in the early stage research and optimization of cellular V2X communication networks and cooperative intelligent transportation systems by providing for accurate virtual modelling, rapid evaluation of system level design and algorithm development, and by offering the possibility to build-up on previous research. Amidst the various architectures under consideration for future cellular V2X, small moving cells or moving network convoys are promising candidates, considering their inherent mobility. The orchestration of such architectures in combination with the availability of precise information about the vehicles from road side infrastructure open up new possibilities for a cost-optimal deployment and a resource-optimal operation of the cellular V2X networks. Towards this goal, we propose and present an open source simulation framework for moving-network-convoy based cellular V2X applications, and make it available for wider use at https://github.com/tum-air/ConvoyV2X.