If you don't have the cash to buy quality parts and do the job right the first time, then I suggest you don't do it at all. The Corksport Power Series exhaust is a favorite amongst many here, as are the HKS SSQV and TurboXS RFL BOVs. In order to install any BOV and have it vent (go pssh) you will need hard pipes at least, or upgrade to a FMIC (recommended) and move the MAF after the BOV so you don't stall. Then you will also need an intake to replace the stock plastic garbage.
And if you do purchase and install all those parts, you will notice that you will get fuel cut every time you actually step on the gas because your engine is breathing much easier now and the ECU is adding waaay too much fuel, so you will then be looking for a piggyback EMS unit to take care of that. It's just the name of the game, cheap and performance don't mix.. not with these cars at least.. and one mod leads to another.