Well I am not familiar with that pump, but it looks like it should be in a museum. I think it is a pump jack type. The rod goes all the way to the bottom and works up and down like a windmill. If so, then it also has 2” galv pipe down the well and it is going to be heavy. The deeper the heavier. You may have all the bolts out and it is just so heavy it feels like it is still bolted down. Probably going to need to lift the whole thing and take the pipe loose below the head. There maybe another flange bolted underneath the head. Jacking it up is a good way to lose a toe or finger. I suggest a good pump hoist.