Where might I find the first mention of cakras as an energetic system used for meditation? How old might these texts be? I thought that a significant portion was developed from Buddhist and tantric praxis? 

I am currently analysing marketing material from yoga organisations to better understand the 'vedic way of life' and 'vedic lifestyle'. There seems to be a conflation of several facets of puranic and upanishadic concepts with 'vedic' into something of a neo-Hindu and/or neo-vedanta 'soup'. Among other things I am interested in what constitutes this particular lifestyle and how it is used to create a sense of authenticity and legitimacy. 

One example, in particular, is the idea of 'vedic meditation'. The picture of a god used in one example seems to have very little to do with the vedic period at all. I could be wrong. Does anyone know which particular god this image is? 

Thanks in advance.