This component is of a special configuration to accommodate the Albion racing gearbox and thus unique to the Grey Flash.
This modification was performed in antiquity but for what purpose we’re not sure.There is an argument that it was done for purposes of lightening though we think it may have been undertaken to enable easier removal of the gearbox.
Certainly, this is an original piece, although altered. To try to replicate the shape accurately without a similar part as a template would be be nigh on impossible.
This part would almost certainly have been silver anodised though it’s difficult to discern now.