Above is a front and rear Redfield International sight set. The other part is the block for mounting it on the side of the receiver of a Pre 64 model 70 or model 52. In fact it will work on a variety of guns. The front sight was mounted using the target block of the day like used by Unertl scopes. These sights were commonly used on match rifles for many years back in the day and while not up to snuff by modern standards, they are capable of some very fine shooting. Below is some of the original paperwork that came with them.