These are the main options for swaps for your year CRX, i know the prices b/c i just checked them out when i was looking for a swap, i eventually did a LS. i wont list parts just engine and price and hp and such.
ZC= 130hp, good reving, decent HP, but a D series engine. $1200( engine and ECU only) non-vtec
B18a= 142hp/122 trq damn good torque rev's like crap. Good build up, cheap
i got mine complete for about $1800 non-vtec ,,,$2500( normally)
B16a= 160hp/111 trq lacks torque, sexy revver, lots of mods, strong starting engine. expensive. $3500 around vtec
b18c = 180hp/127 trq Obd1 wiring, not 0bd0, good of both worlds lots of HP and torque, great engine for daily, can get into 13's without boost. expensive. $4500, vtec
B18c5= Type R engine, great engine, everything is tops, 195hp/???trq. hard to find and expensive. $$5500-6000 vtec
h22a= balls out racing unless u are going to do full suspension swap, 200-220 hp and alot of torque, Harder to Wire, Harder to mount, only for experianced swapper. Great engine if u have the $$. $6000 , vtec
LS/Vtec= 200+ hp and 130+ trq. great engine if made correctly, can b a problem if u are a newbie to swapping. Best N/A engine in my opinion if dont right. unless u can do it urself, expensive to get done. $5000 vtec ( if dont by u)
I advise the B18a or B18c great torque and not to steap of a price.