These parts will let you run a flat tappet cam with the Magnum heads. You don't have to run a roller cam at all and can use the cam you have ordered.
Special length Pushrods: MP# P5007477
Mopar/AMC lifters: Comp Cams #822 or MP4529220
Magnum head bolts: MP# P4876759
Rockers I would go adjustable either SBC with the Crane Cam kit, Crane Rocker Arm Guide-plate Conversion Kits 36655-16 $135 or Mopar kit Magnum rockers, stands, guide plate, and bolts: MP# P4876050 (eight required) non adjustable. Mopar performance 1.7 adjustable kit P5007404 Magnum V8(1992-02) roller rockers 1.7 ratio $569.00