Using an online calculator I came up with this using figures I had and your help. Sound right?
Enter Cylinder Bore Size 4.281

Enter Piston Stroke Length 4.135

Enter Head Gasket Bore Diameter 4.370

Enter Compressed Head Gasket Thickness 0.039

Enter Combustion Chamber Volume In CCs 118

Enter Piston Dome Volume In CCs, Negative For Dished Pistons +3.0

Enter Piston Deck Clearance, Negative If ABOVE Deck : 0
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Calculated Engine Compression Ratio = 8.828691414199347:1
Total Displacement Volume = 124.58558163463904 cc's
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Using the 115cc head as in the question I came up with-
Calculated Engine Compression Ratio 9.021856376087452:1 Comp.
Total Displacement Volume 121.58558163463904 cc's