They're in high demand and fetch a high price, but good luck finding one for sale, most private collectors are unwilling to part with theirs.
As I've been looking around, I've found some quite wonderful pieces and I'd like to share them with you:
These are the best ones I've found on Google - just search ' Victorian era memento mori' and you'll see many, many more. They range from the serene to the bizarre - but that's a post for another day, I think.
I also found numerous boards on Pinterest dedicated to this topic. They have some truly spectacular photos available. If you're interested, check out some of these boards: