If the vaccum gauges do flutter, there is a knurled knob on the pipe which needs tightening up till the fluttering stops. this acts as a damper due to the engine characteristics and is normal on all bikes.
checking my manual, the carbs are the same as the 400 but have different sized jets, so you need to ask them for a 360 kit.
the 360 has; 135 mains, 0.6 air jet, 4FP21-3 jet needle, X-6 needle jet, needle position 3, pilot jet 17.5, starter jet 40.
air screw 1 to 1.5 turns out from stop.
send them an email, as they have tons of stock. if they don't have any try NRP in Manchester UK!