The value on the model as it stands...missing roof-lighter, extra (non-standard), holes, rusty inner baseplate and presumably the outer baseplate covering has gone, it would have had a bluish-green felt covering...is a fiver, if you don't sell it at that, I'll post a fiver up to you for it, tell you what, I'll make it a tenner to cover postage, but as I said in my earlier post above, I do have one of these purchased new, so I'll only have yours if it hangs around your place and nobody shows interest in it.
Ghosty.