I see what Ivan is talking about, and what the other concerns are. Rohm daggers by e-pack have been a mine-field. Also there has been some very good fakes .out of former East Bloc region in the last several years. So, I too have concerns why a authentic (don't know if it is) Rohm blade on a Parts Dagger?
.The repro's have gotten to the point that on e-pack Rohm's I would need a 'Hands-On' inspection to render a opinion.
Also, if advertised on Craig's List or some place like that, be careful. As for $600. it maybe someone else's photos, and you will never see the dagger, or your $600.