A while back, I purchased a small vise with adapter for the Tormach Microarc that I use on my 1100 Series 3. I finally had a job to use it on, and thus mounted it on the Microarc and used it to mill 316 stainless. It was awesome. It was only about $200 for the plate and the vise. I just made 4 parts with it, and which I did an inspection on and shipped to my customer. They were great. Now I can use bar stock on my 4th axis. A nice new capability.
Some key notes. I am not connected with the supplier of this. I just think he made a great product.
I got it from GTM Manufacturing. Here is the link. GTM Manufacturing
Although I used it with 316 stainless, the vise manufacture does not recommend it for steel (does not seem to say anything about stainless steel).
Here are a couple of photos of it at work. Yes there are a lot of chips on the bed. I was in the mode of making parts to meet my deadline. They are all gone now.