The Power Rangers cosplay community really is growing, with people making top quality props, helmets and costumes for all wallets and budgets, but there is one person on the internet that is really making a name for themselves in the realm of communicators:
This is the Starlight Studios communicator, this one being the red ranger. It costs £50 all in from the United States, It's made of real alloy metal all over, with epoxy paint on the banding. It measures about 9 inches from end to end and features a double hinged clasp with locking tongue to keep it on the wrist. The bracelet part can have the links removed or you can buy extras through their site to resize it. You can get the links here.
For the finishing touches, for £16 all in, they also make a SET button that can be glued to the communicator. It's made out of the same alloy metal, painted in yellow epoxy paint and has the word SET with an arrow engraved into it, also painted in black epoxy paint.
This is the only company I've seen making communicators outside of the upcoming Bandai release. As far as communicators go, I do like it. It feels great on the wrist and doesn't move around at all, nor does it feel heavy. The only downside is that they haven't added any electronics, but there are third party companies who will do the modifications for you. If you're interested, you can buy one or any other item they have on their etsy store