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Recently a novel class of scanning near field optical microscopy probes based on an adirectional asymmetry (i.e., an asymmetry encompassing all spatial directions) in form of a spiral-like corrugation has been proposed. Although such probes would entail an impressive simplification in experimental procedures as they allow superfocusing for any arbitrarily oriented linearly polarized excitation, their actual fabrication looks much more challenging compared to probes based on directional asymmetries (i.e., asymmetries lying along one specific spatial direction). Here we propose a new simpler implementation of adirectional asymmetry which shares the same advantages as the one based on a spiral nanostructuring of the external metal coating, while being more feasible for fabrication.