The British Gut Project britishgut.org might be of interest? Single kits cost £75, Double £125 etc.
"British Gut is an open source crowd funded project run by The Department of Twin Research at King’s College London in conjunction with The American Gut project. The aim is to uncover the microbial content within the guts of British individuals. This data will tell us how our lifestyle choices and diet influence our microbiome and how we can alter it to reduce disease and other health related problems. This study will produce a large-scale collection of anonymised human samples and lifestyle information for medical researchers, and provides each participant with a personal bacterial profile of their own gut.
This is a unique open collaboration between the TwinsUK team at King's College London and The American Gut Project (AGP) to try to understand the bacterial diversity of the British Gut.
Many people don't realize that the bacteria that live inside us play an incredibly important role in our health. There are so many of them, that they make up 90 percent of the cells in our body and their most important jobs include "manufacturing vitamins" for us and breaking down and digesting our food. The trillions of bacteria in our gut weigh nearly 2 kg (over 4lbs). This community of bacteria can be thought of as an extra 'organ' which we call our "microbiome". We evolved together with our microbiome over millions of years.
Recent research has discovered that small changes in this finely balanced community can affect our immune system, metabolism, body weight, mood and may even cause diseases such as Crohn's disease, irritable bowel syndrome, cancer, autoimmune disease, diabetes and heart disease.
This is the first project of its kind in Europe and, with your help, we will be able to discover more about the crucial relationship between our health and our microbiome, and on a personal level, you will be able to discover the bacterial profile of your own gut".