Certainly a nice one to have in any condition. If it's even nearly that nice I would have it graded. It's going to be tough, if you aren't used to dealing with high end grading it can be a little disappointing, what might look like a perfect coin to you and me might only come back MS64 or so. I say "only", of course that would be a very nice coin, but at these higher levels it's tiny little things you would barely notice that differentiate the grades. Given this you should really avoid even touching it, put it in a coin slip in something well padded and safe. The book values are always way off but even if it's really just a $10,000 coin a scratch with your finger nail or dropping it on the floor could cost you $1000.
If you like I can put you in touch with the dealer who does most of the high end grading of Australian sovereigns. Very nice guy, very helpful and knowledgeable. If it is very valuable it will cost a fair bit to get graded just because you have to pay insurance on the postage which is a percentage of the value, the actual grading is only about $75. You might think of taking it by plane straight to the dealer of it is that special.
If it is all that and a bag of potato chips would you be looking to sell it? Just that if you were thinking of selling it then other option would be to put it straight into a high end auction like nobles. But having it graded would give you the opportunity to show that it's one of the finest graded absolutely generate a bit of buzz.