Well they all are bolt on swap no alteration stuff required. Though you should replace ECU. I worked out for my 93 accord.
F18B with LSD Gear Box complete 75 K auto and some 85k Manual
F20B Blue top a darling engine with gear box Auto 60k and Manual 80-90k
F23 is below 90k but rarely sold as a whole IMO.
If i was there i would go for F20B swap. A very sweet engine and powerful. From where do you plan to buy it off? lahore? i may suggest some guys