The your paintings archive, which is bringing together digital photos of the entire national collection includes one of Shooters Hill.
At a guess it was painted from the viewpoint of the Tarn in Eltham, or more likely the River Quaggy. Oxleas Meadow is clearly visible, and the hilltop appears more prominently than it does today, presumably due to the deforestation and gravel quarrying that has taken place since. Originally, the crest of the hill lay where the flats in the Cleanthus Road estate back on to Eaglesfield Park, which is itself now the highest point on the hill.
If by some stroke of luck you find yourself near Glasgow Museums, why not pop in and see if they have it on display?