Thanks guys for looking at your actions and posting what you found. I have done some research on this and my question hasn't yet been answered to my satisfaction but I know more than I did.
I went to a Tulsa gun show and looked at about a dozen used model 7 rifles of various ages and configurations. Some of them had the slot cut in the bolt lug and some of them did not have the slot. None of them had a rail.
I stopped at a local retail gun store that usually has a considerable amount of Remington rifles. They had one new Model Seven in 300 Blackout. It had a slot and a rail.
I called Remington. The first person I talked to didn't know what an anti bind rail was so they transferred me to a technician. That technician didn't know either but luckily he had a genuine desire to help. After I described what I was talking about, he put me on hold for several minutes. When he came back to the phone, he said he is holding in his hand a model 700 action and that he sees exactly what I am talking about. He also says there is another technician there that is a Model Seven nut, collector, guru, and if I would give him my number he will see if he can find that guy and call me back. About an hour later he calls me and tells me that he found the guy that knows everything about a Model Seven and that guy said every Model Seven that had ever been built had the slot and anti bind rail. I told him his expert was wrong. He laughed and said if he could find out anything else about this he would call me back.
That was a couple weeks ago. I haven't heard from him and don't expect to.