I am not an accountant (IANAA), but what about the following:
a. Company buys, but then silver dips by 20%. Company sells at going price + VAT so now holding is personal rather than company for same total cost. Note that as a director, you have a duty to maximise profit for your company, so this could be viewed as a bit "dodgy", but with current cashflow issues that many companies will be facing not something that should raise flags.
b. If silver rises, then at least you have delivery and you can still sell in the future. You could sell at the cheapest price you can (what is the cheapest competitor?) without delivery risk.
c. If you wind up the company, then redundancy payments have a tax free element, so you can take advantage of this when liquidating assets