If you can get some heavy rail here is a great idea for a post anvil. You may have to look around and call the rail maintenance yard, but the heavy rail is twice the size of regular rail. big industry and ship yards have rolling cranes and equipment moving on it. Some of the really big stuff has a rail face the size of a standard anvil. When you find the piece, try and get enough for a 24-30" piece and a 12-16" piece.
The post anvil should have the face a tad higher than a work anvil. About 36" is good.
Get a small galvanized trash can about 24" tall. Find a piece of steel plate that will fit in the bottom of the can ( it doesn't need to be round, square is fine). 1-2" thick is great, but even 1/4" will work. If needed, stack several sheets to get the anvil top about 36" high. Center the rail on the plate and brace it vertical. Pour the can full of concrete and let cure. You have a basic 200-300 pound post anvil.
Now comes the fun - a hand held 3" belt sander with a metal cutting belts and an angle grinder will help a lot here.
Grind the top rail part into a small anvil face. Make it smooth and flat.
Grind the web into a rounded drawing/fullering die. It should be smooth.
Grind one side of the foot into a flat and square edge for bending and striking plunges.
Grind the other side of the foot into a 45° angle for cutting. It should not be too sharp, just an even and minutely rounded edge.
You will be amazed at how well this post anvil will perform 90% of all forging tasks.
Next project, take a 12" section of the same heavy rail type to make a flat work anvil.
Note - If you have a friend with a machine shop or large mill, have the face milled flat first.
Pour a matching trash can of concrete so the face will be about mid-wrist high. You want to pour it so the anvil will be the right height when set on the concrete ( do this in layers if needed). Once you are up to the right concrete depth, let it set a bit, place the anvil on the mostly set concrete, and wiggle it to make sure it seats well.Checking that the face is level. Then pour two more inches of concrete to lock the the foot solid. The final step is to grind the rail face flat and smooth. With this two-piece RR anvil set, you can make most any blade you want.