The only thing I can think of any time I see a SM head :) The perfect solution for anyone looking to bypass the abominable intelligence!

It's a conversion kit including a torso, an abdomen, the pauldrons and the cupola. It looks very minimalistic, but trust me I added some details ;) You can either keep the backpack or stick a riot shield on his back like in the manga.

I just took some liberties with the pauldrons so you can easily merge any insignia on its flat side and the belt, if you want them to integrate a mechanicus force. So grab some marines' pieces, prepare your adrenalizer and let the dogs of war loose !

You'll find a genuine looking pauldron here but not really suitable for PSM backpacks.
The Socket soldier's true pauldron
An other one built from scratch and not imperial looking, the best and closest to the manga in my opinion.
The Socket soldier's pauldron reworked
Here's also Wombat's excellent riot shield, fits the look so nicely I don't think I'll have to do another one.
The riot shield

(The cupola and abdomen are the only parts really needing some supports. It is primaris sized, scale down for classic SM compatibility. Depending on wich head you use some might be to big to fit in the cupola and will maybe require a light filing. The rest of the pieces used for the renders come from the excellent kit of Joeld93)