CG13's are less than that with a 'general' setup. More like 98bhp with stock cams, exhaust and pod filter on a dyno which isn't on the generous side, less with the stock airbox and panel filter. You've got to do quite a bit of work to push through the 120bhp barrier.
Re: turbo kits, there aren't any specific kits any longer. HKS discontinued their low boost kit and Kappatsu are long gone also. Someone on here was selling an HKS turbo manifold though. Like most thinks K11, you're pretty much into custom territory if you want big power.