ciphergoth | Sealable collars without buckles?

I'm looking for ways of making a collar on which I can make a tamper-evident seal, such that you can't take off the collar without breaking the seal. I'd like it to be suitable for long-term wear.

My first thought was to take an ordinary fashion collar, and seal the buckle with sealing wax. The trouble with this is that buckles tend to catch long hair, especially when you sleep. So here's plan B: use a plain wide black satin ribbon, pin it shut with a couple of small safety pins, then put the sealing wax on the safety pins. But I worry the wax might be too brittle.

Any other ideas very welcome!