I'm sure it would do the jobs you describe just fine. It's a pretty basic machine, made to compete with the little Unimat lathe, and some examples are not of brilliant quality. Here it is at £191 inc. carriage from Arc Euro Trade, which is, like Axminster, a reputable dealer:
http://www.arceurotrade.co.uk/Catalogue/Machines-Accessories/Lathes/C0-Baby-Lathe There's a link on that page to a review, which I've read. It might be a bit too enthusiastc.
Some cutting tools will be needed. You mentioned brass, which requires a particular profile on the end of the tool for best results. If your camera work also involves aluminium, a different profile is needed. You would probably do best to grind your own tools out of HSS (high speed steel) blanks, which will involve getting a grinder (one expense leads to another with lathes

) . For reasons too involved to set out here, it might be wise to avoid carbide tools.
You mentioned that holes might need drilling; looking at the shape shown in the photo you posted in the previous thread, I doubt if this lathe will be much help on that score.
As to second-hand stuff, someone may come up with something. Unfortunately I don't want to sell it, but I've got a baby lathe which would do the job perfectly:
http://andysmachines.weebly.com/perris-baby-lathe.html 40-odd years old, and still going strong, though I did have had to do major repairs on its headstock three years ago.
Andy