So with stock shocks/springs, at stock height, without slotting, -3 camber front is possible even with rubber top mounts.
SPC 81305 camberbolts lower hole, Whiteline KCA416 ones in upper, Whiteline KCA434 LCA bushings anti-dive kit for slight extra caster, Powerflex PFF69-801G LCA bushings for extra camber, (non eccentric) Subaru group-N topmounts:
But it's about max for front camber (~ -3.1dg), so if more is needed, camberplates or lowering or slotting probably is unavoidable evil for extra camber.