depends on what you want out of the upgrade, like any other performance upgrade, $$$ is the stepping stone.
at minimum I would replace the rocker arms, they wear "burnish" to the cam in the first 30min of run time, installing a new cam with old rockers is a pretty good risk of wiping off the cam lobes in short order, even if you properly break in the cam.( 20-30 min sustained 2000rpm, keep the oil flowing over lobes and followers, lobe and follower should "burnish" to each other, and work harden.
I've done cheap, medium and expensive cam upgrades, cheap one lasted about 15k miles before 2 lobes were wiped off the cam ( reused the original rockers ) , next was new cam, new rockers and valve springs, along with a 3angle valve job, much better performance, over 100k before I sold it, the expensive was new head ( with performance valve springs ) cam, rocker towers, rocker shafts and new rocker arms/cam followers, adjustable cam timing gear (degreed) . ran well, but could have been better, sizing the towers to center the followers on the lobes would have helped a bit, but I didn't have time or the extra cash.
the last two cams swaps in 22re were LC Engineering, worked well with OEM fuel injection and a mildly modded air flow meter. LC Engineering long tube header, 2.5" cat 2.25" pipe and flow master 50 series muffler. Ran well, sounded good. YMMV
