oil pans, water pumps, timing covers

[23TrackroadsterV6]

I have a 3.1 from a 1991 Isuzu. I know it has the reverse rotation water pump and timing cover. I would like to change to standard rotation water pump. What year and model timing cover do I need to use to be able to stay with the oil pan I now have? What water pump is like the ones pictured? It has screw in heater hose outlet. Does anyone know of a 6 rib water pump pulley that fits? I know I can buy billet aluminum ones from one of the British car swap sites, but at almost $200 they are a bit pricey. I want to run a setup similar to the attached photo, only use steel pulleys.