99CIVICEXB18

Hey new to the site join because I heard it is very helpful but enough with that!

I drive 99 civic ex but I did a b18b i think thats right out of a 99(LS integra)
I have changed the suspension
changed the exhaust system
about to change the header
changed the clutch to Stage 3 racing
cold air intake

I'm now out of ideas on what to do next to my car so can you give me some ideas that would be helpful in helping me gain somewhere from 50-100 hp!

Should I change my head to Type R someone told me that but I'm really trying to see from 50-100 hp increase so can you guys give me some ideas?
My cash limit right now is only $1500 to spend on parts now so can you work in that range!
Thanks