Car template is here: http://www.imagespaceinc.com/downloads/rf2/paint/car/ISI_Dissenter_Template_2016.zip From this page: http://rfactor.net/web/rf2/rf2dl/
My apologies, I didn't read it right. Are there any helmets that work from the Modding Resources (Cars) section? http://rfactor.net/web/rf2/devscorner/ It might be using the default templates, I can't remember.
Unfortunately no, the helmets in the Dev Corner are all the modern helmets. The Dissenter uses a helmet without a visor. It seems ISI did add wchelmet for a material name, but never released the template for use.
Here is the dissenter helmet: https://s3.postimg.org/yy37zdq6r/dissenter.jpg Here is the Eve\Spark helmet: https://s9.postimg.org/wiwzqn2wf/spark_eve.jpg