If your simulation does not need to model any of the higher-layer functionality of DSRC (like channel hopping and service advertisements), you should be okay with using the INET Framework's 802.11 model in 802.11p mode. See the Veins_INET subproject - e.g., at https://github.com/sommer/veins/blob/veins-5.2/subprojects/veins_inet/examples/veins_inet/omnetpp.ini#L14 - for how to do that.