stock ecu is fine when CHIPPED.
Easiest and by far the cheapest standalone setup is a speeduino with the $45 OBD1 plug and play adapterboard. Depending on deals, you can be in for under $500, and including the cost of the AEM UEGO you seem to have bought.
stock 240cc injectors are good for an absolutely blistering 150whp or so of power before they start to have trouble. You can go further, but not worth the risk of leaning out.
If you need injectors, I have a set of ID 600's, else I highly recommend finding a set of OEM honda RDX 410cc blue injectors. They flow more than 500cc at 60psi of rail pressure. Stock fuel pump is going to be hurting, so a walbrto 190 is a great drop in, supports over 400whp boosted, and is rarely fake-manufactured, compared to the more popular Walbro 255 pumps.
Else a stock hellcat fuel pump can be found on ebay with a wiring harness for $150. Easy to source, plenty reliable, and proven to handle very high pressures.