@Chris MacDonald @Giray Izcan @Kevin Neal Thanks for the responses! In the Process of Building, I actually found a Video tap.
I am just not 100% sure if it fits on the sr1, you guys got any experience with that and also how to power it, I tried looking for a 11 pin battery but I haven‘t been lucky yet. https://www.willhaben.at/iad/kaufen-und-verkaufen/d/arri-arriflex-sr-video-ausspiegelung-cinegate-546668593/