Yeah, that is different than on my 450. On my 450, that bottom piece has a slight slant in it on the end that the handle screws into. On yours it looks straight across and the handle itself is bent.

If you have access to an oxyacetaline rig, I don't see why you couldn't buty a rosebud to a roller handle (with the roller part not screwed on) to heat and bend a handle though. Clamp the base of the handle in a vise, apply a rosebud to the handle low down where your present handle has the bend, heat and bend it as needed. Then let it cool down and spay with some paint to protect it.