Kohlswa anvils are nice, I have two of them I bought new when I started full-time blacksmithing 35 years ago. At the time they were sold by Bill Pieh at Centaur Forge. They did have a reputation of being soft when new but if used carefully they would work harden after enough use. Yours looks...
It is likely part of the 4-piece Pexto (originally Peck, Stow & Wilcox Company) set, #949 for forming sheet metal. There is a long holder that fits into a big stake plate and three forming tools that fit the end of the holder. I don't believe this will fit directly into a Pexto stake plate...
A lot of anvils were made with a wrought iron body that had a steel work surface forge welded to it. Some anvils were even forge welded together from six or seven pieces in layers. Over years of pounding, the softer wrought iron can sag while the steel face stays straight, leading to...
It is undoubtedly a Trenton as their logo was the name "Trenton" inside a horizontal diamond frame, both of which are visible in your photo. If you have access to the book "Anvils in America" by Richard Postman, there is a good section on Trentons which were made by Columbus Forge and Iron...