Question---If I have a 99 RS and remove the sight, do I now have a 99 R?

RS had sling and swivels too. Going elk hunting this morning.

1950's 99RS Version 2, or 1930's/1940's 99RS Version 1?

1930's no - as David said they also had very uncommon studs.
1950's yes - the peep sight was the only difference.

They also came with the Lyman #6 folding leaf rear sight.
saw some elk this morning in no-no land. At least some are down out of the high country. Now they need to come to where I'm permitted to hunt.

Do you have any snow? When does season end in your unit?

no snow yet but will get some tonight. Bull season ends 10-31, cow/calf 11-30. Wife called and told me to put the snowplow on the truck, she said we're getting 16". The weather reports I looked at said 1" tonight and a few more tomorrow and Sunday.
I'm going out again this afternoon and see if they have wandered over to where I can shoot one. If we get 16" it's going to make the hunting really hard. She's at work or I would call and ask where she got the 16" figure. Some people around here like to tell windy westerns and I'm thinking that 16" bull is one of them.