Here's what I use...I'm not sure how large your need is, but we provide this service to a number of companies, so volume is an issue for us as is price, that sort of bit. Our need obviously differs from the need of a company planning to do their own labels, in sort of a one time deal.
That being the case, I still recommend what I have been using. Graphic Products from Oregon sold me a Duralabel 4TTP and label stock for a reasonable price. The software that comes with it allows you to print all sorts of labels, not just arc flash labels, and the printer will accept any of a number of different label stocks, from 4x6 "WARNING" header arc flash labels to generic orange 2 inch wide tape. Additionally, the printer interfaces your PC via a USB connection, and will print and cut the labels or print them without cutting. No, this isn't a compensated endorsement. They have treated me very well and as an added bonus, they ship M&M candies with every order. I'm serious about that part. I have an office mate who stands by our door salivating every time I order new label stock.
A link to their website is below. I know this isn't what you asked for, but this printer setup works really well, and the labels are weather and chemical resistant, and look great. We've done arc flash analysis in 6 states, dozens of companies and they all love the labels. I hope I've helped.
http://www.graphicproducts.com/
