Yeah, I can see the deathdealer link, but I think the connection has more to do with the combined posture of the horse and rider, with the rider sitting back in the saddle as the horse goes down a slope.
To my mind it's got more to do with the Warmahordes sculpt of Captain Kayne.
I don't know, I'm pretty sure I've seen an old masters type painting in a very similar pose, but it could just be the onset of senile dementia.
Thanks for the help folks.