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The current generation of experiments aiming to detect the neutral hydrogensignal from the Epoch of Reionisation (EoR) is likely to be limited bysystematic effects associated with removing foreground sources from targetfields. In this paper we develop a model for the compact foreground sources inone of the target fields of the MWA's EoR key science experiment: the `EoR1'field. The model is based on both the MWA's GLEAM survey and GMRT 150 MHz datafrom the TGSS survey, the latter providing higher angular resolution and betterastrometric accuracy for compact sources than is available from the MWA alone.The model contains 5049 sources, some of which have complicated morphology inMWA data, Fornax A being the most complex. The higher resolution data show that13% of sources that appear point-like to the MWA have complicated morphologysuch as double and quad structure, with a typical separation of 33~arcsec. Wederive an analytic expression for the error introduced into the EoRtwo-dimensional power spectrum due to peeling close double sources as singlepoint sources and show that for the measured source properties, the error inthe power spectrum is confined to high $k_\bot$ modes that do not affect theoverall result for the large-scale cosmological signal of interest. Thebrightest ten mis-modelled sources in the field contribute 90% of the powerbias in the data, suggesting that it is most critical to improve the models ofthe brightest sources. With this hybrid model we reprocess data from the EoR1field and show a maximum of 8% improved calibration accuracy and a factor oftwo reduction in residual power in $k$-space from peeling these sources.Implications for future EoR experiments including the SKA are discussed inrelation to the improvements obtained.

A high resolution foreground model for the MWA EoR1 field: model and implications for EoR power spectrum analysis