Nope, and definitely not going to be something you can modify to make work either. NOS forends, for either the No.1 or the No.4 are rare as hens teeth - other than arsenal refurbished/well worn forends that seem to be available for the No.4 Mk.II.
If you're in a pinch, find yourself a reproduction wood set; as it'll set you back less money than NOS and you'll actually be able to acquire it in a reasonable timeframe.