I've got receiver sights on all my Rugers except on my .22
The top rifle is a MKII .30-06, CRF with factory original sights and is drilled and tapped for a Williams Foolproof receiver sight like the one on the rifle pictured below it. I had it removed at the time this pic was taken.
Center rifle is the first stainless rifle I bought, a MKII 30-06 push feed, either late 80's or early 90's (poor memory!), before they were available with factory sights, so I purchased direct from Ruger a barrel band front which I installed along with the Foolproof shown mounted.
Here's a closer view of the front sight on the center rifle
And the FP on the same rifle
Now that the Scout rifle has appeared, I naturally had to have one of those too
Pics of your rifles with receivers sights will be very welcome!