769. Determination of profit or loss in respect of asset where records incomplete

In determining for the purposes of this Part whether a company has made a profit or loss in respect of an asset where—

(a) there is no record of the original cost of the asset, or
(b) a record cannot be obtained without unreasonable expense or delay,

its cost is taken to be the value ascribed to it in the earliest available record of its value made on or after its acquisition by the company.