Our wonderful german customs denied the import of the new Sigma AV1 supergun i bought from tops-game

CE sign missing, no german manual, no german current connector etc. this sucked big time.
Anyway, bought an older model the AV5000 from a fellow member from otaku.
1.) I wonder if it is possible to easily change the PSU on this beast, since i dont want to use a step-down converter (ordered 300W model; down to 110V)
2.) Wont 110V-115V damage the SG in the long run since its labeled to be used with japanese 100V ?
3.) I hunted the right Stick for it (TB8000), since i dont like the cheap neo-geo sticks. Unfortunately with no cables, will any D15 <=> D15 cable fit ?
4.) Can i use this cable for example? https://www.amazon.de/SVGA-Kabel-Premiu ... s9dHJ1ZQ==
BR