I found steel retractors in the shape of the plastic ones I like. These are two handed (patient controls the tension; can't blame you for being rough) and have large and small ends. Unlike the plastic ones, they won't melt in your autoclave. (and if they do, you have other problems)
There's also a black stainless steel version. This appears to be either painted or anodized. They were piano black glossy when I first got them, but autoclaving seems to have added a patina to them. It does rub off, but I prefer leaving it matte to reduce the slight glare you see on these photos. I wish it were black silicone; that's my favorite surface finish for black anterior contrasters.
Search for stainless steel lip retractors on e-bay.
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Search for the black stainless steel cheek retractors on ebay.
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PS What about the stainless steel Columbia retractors I used in dental school?
I used to use Columbia retractors. Advantages: The Colombia is VERY durable --should last your entire career. It also easily retracts without interfering with occlusal mirrors or buccal mirrors. The downsides are it's VERY bulky to sterilize and it looks very "gynecological" / "medieval" in its appearance. I switched to Columbias entirely for a few months, now I'm switching back to this shape. It's personal preference; there isn't a "wrong" answer as long as you get the image you want, and your patients don't flee you in fear.
If you're in a fast paced clinic where things get beat up, definitely consider stainless steel retractors over plastic ones. It will definitely cost you less in the long run.
Photomed has an excellent collection of retractors. They are amongst the only ones who sell round ended Colombia retractors.
http://www.photomed.net/retractors.htm