4 Vise Capital D Within circle With Swivel Bass Very Nice 51-lb smooth jaw

I have done some research using google, Garage Journal and a couple of other sources, and I have found very little that the vise has a capital D within a circle what I found was that it is rare. There were some guesses it looks like it may be. There's a ranch with a capital D, could it have been made a brand? With at swivel base 9"and w jaws 4" The throat opening is 5 and it is 48 lb it is a smooth jaw vise. There are no cracks, chips, or welding. It does have normal wear for its age. Please look at all of the photos. It's a very nice original piece.

I have posted this with the best offer. If this is something that interests you, make me an offer based on what you think.

It's worth or what you're willing to pay for it all I could say is no thank you. If you have some questions or you need more photos, don't hesitate to ask. Thank you for taking the time to look, Michael.