Some useful websites:
https://www.fightbladdercancer.co.uk/
https://www.theurologyfoundation.org/
Healthcare companies for catheter & stoma supplies
You are allowed one prescription a year for stoma underwear, here are some websites
https://www.salts.co.uk/en-gb/products/additional
Travelling with a stoma? What you need to know
https://www.securicaremedical.co.uk/blog/travelling-with-a-stoma