Well I did mean USDM B20B or JDM B20B since you'll be using NOS, but since you'll only be using it on the track it might make more sense to get the higher compression one. Not all JDM B20B's are 9.6:1, my friend bought a '99 JDM B20B with the LS style intake manifold and it had the P3F pistons in it which makes it an 8.8:1. Bummer. All the dudes on the internet are wrong. Your best bet is to buy a B20Z, thats it!!!
As for not having the money, I hear ya man, but believe me, once you get into it, you start saying "well I'm going this far, why not go this far". i.e. you get cams, then you get convinced you need springs, so you get springs. But retainers are a good idea, so might as well just get them too. Now your getting a valve job & new valve seals etc, it'd be wrong to use stock valves wouldn't it! Your getting headwork, what stage etc... Same goes with the bottom end. Unfortunately my bottom end is stock for this year, but I will be investing in it next winter.