Its not about what they are worth yet. You first need to establish he had no right in taking them and selling them elsewhere. I'm assuming you are pretty confident of this factand hence why you are asking everyone there opinion but our opinion doesnt matter, we ae not quailified people in the area of green trees, and probably never will be unfortunately.
Here is something to consider 'HERESAY'
EVIDENCE ACT 1906 - SECT 79C
Documentary evidence, admissibility of
79C . Documentary evidence, admissibility of
(1) Subject to subsection (2), in any proceedings where direct oral evidence of a fact or opinion would be admissible, any statement in a document and tending to establish the fact or opinion shall, on production of the document, be admissible as evidence of that fact or opinion if the statement ?
(a) was made by a qualified person; or
(b) directly or indirectly reproduces or is derived from one or other or both of the following ?
(i) information in one or more statements, each made by a qualified person;
(ii) information from one or more devices designed for, and used for the purpose of, recording, measuring, counting or identifying information, not being information based on a statement made by any person.
(2) Where a statement referred to in subsection (1) is made by a qualified person or reproduces or is derived from information in a statement made by a qualified person, that person must be called as a witness unless ?
(a) he is dead;
(b) he is unfit by reason of his bodily or mental condition to attend or give evidence as a witness;
(c) he is out of the State and it is not reasonably practicable to secure his attendance;
(d) all reasonable efforts to identify or find him have been made without success;
(e) no party to the proceedings who would have the right to cross-examine him requires him to be called as a witness;
(f) having regard to the time which has elapsed since he made the statement and to all the circumstances, he cannot reasonably be expected to have any recollection of the matters dealt with in the statement;
(g) having regard to all the circumstances of the case, undue delay, inconvenience or expense would be caused by calling him as a witness; or
(h) he refuses to give evidence.