Calmini and 4x4parts.com both make the best 3" lift you can get for a gen 1 Xterra. Both are around $1,000.00 for everything needed. With the Calmini kit however, stay away from their branded shocks. They are shit. Get the Bilstein shocks. They are the best out there for a gen 1 Xterra.
on a gen 2 you can fit 33" tires without doing any kind of lift. some people have to push back a small bubble in the plastic in the fender so that the tire doesnt rub on it. thats the melt mod. heating it up and pushing it back.
You can use front spacers and shackle lift. RC and Calmini have this kind of suspension lift system that fits your budget but the gain is up to 2.5" lift only. Nisstec has coilovers + AAL lift though it is bit pricey.
Has anyone done 2" spacers with adjustable quick lift shocks on front to achieve 3" lift?? Currently have 2" spacer and uca's. wondering if I could get that extra inch of lift by replacing the shocks with adjustable height ones. Thanks