I picked up a couple of those, and they don't appear to have any instructions included with them. Here's a thread of one of the assembled ones. Most likely you'll have to mock it up, do some sanding on the triggers and other injection points, paint as you see fit, and then assemble.
Here was an assembled one that a fellow RPF'er posted, might help with assemble and areas to paint.
I was lucky enough to snag one of the Tomenosuke Blade Runner Blaster Chibi, and it arrived yesterday! This is a static, fully-assembled piece. There are no moving parts. I think the piece is very well done! The finish is fantastic! The upper receiver is matte black and the ammo clip and...
also there were some brief comments/pictures of assembly on the owners blog...
I don't think you really need an assembly guide for these. The sight rod glues on where the sight rod usually goes, the grips glue on where grips usually go, the barrel support glues in where the barrel support usually sits, the Weaver knob.... I think you get my drift.
Unless you have no prior knowledge of Blade Runner gun design it's all fairly obvious.
One of the comments on Tomenosuke's retailer blog was about the build I did of a Mod CHIBI;