The ones I use the most are the ones sold by a major supplier here in the USA. I believe they are manufactured in Taiwan.
You can check out and join Alibaba.com and get plenty of information and help on buying just about any kind of imported product you can imagine, including custom work. You post what you want, and suppliers will contact you. I have used them to order two products I use regularly: a custom-made Texas Ranger-style concho and some very nice gift pouches for pens.
The downside, as I see it, is that manufacturers in Taiwan, China, India, etc. have gotten wise to pricing, and the good deals aren't as good as they used to be, plus their minimal orders can be pretty stiff, tying up a lot of cash. On some things, you can do almost as well, and order in smaller quantities, through eBay.