Rumor has it that the new complete box set and the smaller Collection 6 set of Poirot, due out here 10th April, will have Sid's episode on. However I have been unable to find any listings for these sets, except that the smaller set does include extras. I found the suggestion that the episode might be on these sets here.

messageboard

It's the message from Adam1983.

P.S. It takes a while to download.