you may want to try out @Nothern Garage in Sg. Ara ... the boss is very friendly and the price is very reasonable too (don't get scare off with some evos or wrx in the workshop)
There are quite a number of boost controllers available in the market. Perhaps I would list down a few such as HKS EVC, BLITZ Dual SBC Electronic Boost Controller, Apexi AVCR Boost Controller, SARD...