  Emission from high-$z$ galaxies must unquestionably contribute to the
near-infrared background (NIRB). However, this contribution has so far proven
difficult to isolate even after subtracting the resolved galaxies to deep
levels. Remaining NIRB fluctuations are dominated by unresolved low-$z$
galaxies on small angular scales, and by an unidentified component with unclear
origin on large scales ($\approx 1000''$). In this paper, by analyzing mock
maps generated from semi-numerical simulations and empirically determined
$L_{\rm UV} - M_{\rm h}$ relations, we find that fluctuations associated with
galaxies at $5 < z < 10$ amount to several percent of the unresolved NIRB flux
fluctuations. We investigate the properties of this component for different
survey areas and limiting magnitudes. In all cases, we show that this signal
can be efficiently, and most easily at small angular scales, isolated by
cross-correlating the source-subtracted NIRB with Lyman Break Galaxies (LBGs)
detected in the same field by {\tt HST} surveys. This result provides a fresh
insight into the properties of reionization sources.
