Someone suggested making your own Cadre Fireblades from unused Ethereals from the Start Collecting kit and that's what I did. I've added a sword, hands, head and backpack from the Firewarrior/Breachers sprue and it looks quite nice imho (I'm not fully satisfied with his left hand but I had no better left hands left ).
The thing is - I don't think the parted robe looks all that good. You can look up his skirt with that hole in the middle. Would you suggest anything? I'm not that good at modelling so making the missing part with greenstuff would probably produce a mediocre effect at best :/
Chop the left arm just below the elbow before the armlet and rotate it about 90* and cut off the scanner. Try to keep something resembling a finger or just make it a fist. Not sure what you're talking about with the robe since it's not clearly photographed in the picture but if it bothers you, try and maybe cut some armor from a firewarrior and glue it in.