I have a 01 dodge ram not sure what to do with motor?

hey i have a 01 dodge ram sport 5.2 the motor has a knock oil pump went i got a new oil pump and im getting my taxes back dont know what to do motor wise i was thinking about buying a hemi and a hemi trans and puting that in but i dont know what the labor cost would be or what all i would need to do to to it i was also thinking about makeing a 390 stroker out of it but i dont know what the mpg would be around with the 318 now im only getting 12 mabe 13 with 160000 on the motor or i could get a 360 and put that in can anyone tell me what would be the best thing to do the truck has a 3 inch bod lift and 35 inch tires trying to get aleast 15 or 16 highway can anyone help me out