Hi
I can help you get this project produced. I can advise to use PETG for durability and cost-effectiveness. My quote is based on this material, for 500 pcs and including all extra costs like shipping/VAT. My proposal is that I first send you a small batch, 2-5 pcs depending on your choice. If you like the result and order the rest, you don't have to pay for those. If you decide to go with someone else, I'll charge 15GBP for producing and shipping those.
But I'm sure you won't be disappointed as I can produce such parts with high quality. It might take a little bit longer as some others, but hey some things take time. Like manually checking all parts if they're good enough and don't contain irregularities.
I hope to hear from you soon, I'm looking forward to help you out with this project.
Sincerely
Kasper Daems