Buy 2 piece head separately?

Recently I bought a new handle for 3 piece razors. My plan was to move the head from a dormant razor to it and away we go. It works, but I'm finding it's not ideal. I've done a bit of looking online, but have not found anyone who sells just heads. 

Does anyone know of a vendor who sells heads by themselves? At the moment I'm not too hung up on open or closed comb.

Thanks in advance.

Dave