further to your most recent response, the fact that you fail to indicate where you live has brought about this situation. It may have come to your notice that both myself and 'stretch' clearly indicate in which country we reside
If you mention CIA to me, I am going to assume you mean the company that operate out of the Channel Islands (Located between Britain and France). Hence the reason I mentioned that you could obtain a PSU more locally in the UK.
As I previously stated (in case you failed to grasp it), you need to know P R E C I S E L Y what Channel Island Audio mean when they quote "a 2.5mm diam plug" . . . . is this the internal diameter, or the external diameter? You also fail to mention the length (which for the Soundbridge is very critical, as it must be at least 10mm long).
Having now "spoon-fed" you with all this info it is hardly rocket-science for you to now resolve the answer to your own question by emailing the CIA and requesting T H E I R confirmation.