I thought you only wanted them for a HC so just install, use, remove, no?
I can't find a link to the ones I have. They existed when I was still in Oz and I bought another set in the UK many years ago. I think they still have the original button cells in them!
Those look ideal. £3.72 for lights, £13.06 shipping :I
Trying to avoid the silicone ones as they tend to get switched on in a kit bag or on the bike, emptying the batteries.