PP is a very good oil, check the UOA section, you might find some with the same engine as yours.
Mobil1 filter is higly regarded here and in the UOA section, I think a Tundra owner showed us that its filtration is really good (he did particules count by sizes).
I will say you can go easily 7500 miles, especially with your driving and maybe even more after checking with an UOA.
My 2 cents, go 7000 miles, do an UOA while keeping the oil in the sump, and depending of the results, go longer or not.
More experienced BITOGERs (I am still novice) will probably chime in and be more detailed than me.
What is your car, how many miles?