Looking for an Imperial order-in-council - any British dopers care to help?

Factual Questions
1

I’m trying to track down an imperial order-in-council from Victoria’s reign. It was never gazetted, because it was issued under the prerogative, not under the authority of a statute, and the gazetting requirement only applied to statutory instruments.

What office in the British government would be responsible for keeping track of orders-in-council? Here in Canada, at the federal level it’s the Privy Council office. What would be the equivalent in the U.K. - Privy Council office? Cabinet secretariat?

And, given its antiquity, I suppose there’s a good chance it’s now in the Public Records Office. If so, would it be filed according to the department that recommended its passage (in this case, the Colonial Office)? or by the central Cabinet secretariat / Privy Council office ?

Any thoughts, bright ideas, interesting comments welcome.

2

If it’s not too obvious a suggestion, have you tried searching the online catalogue of the National Archives (as the PRO insists on styling itself these days)?

3

I tried that, but all I found was list of series of documents, with pretty general topics. Since I don’t know if it’s a Colonial office document or something else, those lists weren’t much help. Unless I’m missing something and somewhere in there are indices to the actual documents?? I’m not familiar enough with the PRO (as I insist on calling it :wink: ) to know where to look.