It looks like the KT-R1C is getting closer and closer to finally becoming real. According to Lei on the RGHANDHELDS.COM Discord, the approximate weight for the metal variety will be around 320g. I would have preferred Stacked Shoulders myself but this might still be a pretty awesome pocketable option!
When it becomes available for pre-order, more info should appear on their site:
Below are some new production images of the handheld assembled with an aluminum shell (colors are not final):