I'd been thinking about doing this for quite a while, and finally ordered one from Brownell's. They've got blued steel or stainless, since the frame is stainless I went with that.*
The reviews mentioned that the surface needs finishing, and it certainly does. I used some 240-grit wet/dry paper to clean up the surface, then some buffing compound and a felt wheel on a rotary tool to polish it a bit.
Extended safety had before on the left, new one on the right
Note: I had to do some finish work on the back as well, as it was a bit uneven.
On the fitting, it took very little to make it work properly, probably spent as much time smoothing the back as I did fitting the safety lug. Here it is installed
So I give this a definite thumbs-up. If you have small hands, or the same arthritis problem I do, I'd suggest you consider getting one.
Remember: unless the thing drops in and works correctly(sometimes they will), then some fitting WILL be required, and if you're not certain about how to do it and your ability to, take it to your friendly gunsmith; you do NOT want to try this unless you're sure of how and your ability to do it.
*Wilson Combat also makes one in blue, but from the pictures the shelf isn't as low(which might make it just right for you, that's your decision).