Yes - a professionally rebuilt one will cost you anywhere from about $60K - $200K. Once in a you will find a fully restored one for less than $50K. Toss in the fact that the one pictured in the OP is not a common one the asking price is really good.
The question is - why would you want to buy one that has been fully restored, especially at those prices? Why not just purchase one from a reputable dealer or private individual? You can checkout the pricing on eBay to give you a general idea. Better yet, just Google something like "Land Rover SIIa for sale".
They are easy to work on and parts are not hard to get.
I'm an idiot when it comes to auto mechanics and even I'm almost done with a complete chassis off refurbishment. I've done all of the work myself with very, very little physical help. I have gotten tons of help as in advice, tips-n-tricks, and opinions; the Landy community is more than willing to help out! The only physical help I've had so far is pressing distance pieces and races before I bought a shop press; sandblasting parts for painting; having the body panels professionally painted; and moving parts that are too awkward to move by oneself. I will be getting help in installing a new electrical harness and the rest of the electronics, my father-in-law is going to help do it.
Other than what I said above I've done all the work myself. I've rebuilt all three gearboxes that make up the tranny, rebuilt the brake system; rebuilt the drive train, suspension, hubs, steering system and so on.
If someone like me can do it anyone can. There are many out there for sale that don't require a lot of work and there are some that do. Mine didn't require all of the work I've done, yet it will go a long ways in regard to use and longevity.
Still...they aren't cheap. The more "quintessential" ones, like mine - a '63 SIIa 88 Station Wagon with Tropical Top, are going up in price. The older they are the more expensive they can get. The Defenders ALL tend to be pricey.
I got mine for $5,500 13 years ago; today if I were to buy it, in the same condition it was in when I got it, it would go for about $10K. So far I've invested about $8K in parts, not counting the cost of sandblasting and painting. The painting alone cost just a bit more than I paid for the rig.
I chose the route I took so that I could do the work myself and make the Landy my own. I also did it so I would learn to work on it myself.
Something else about buying a fully restored one vs one that isn't...the community tends to hold those who buy fully restored in less esteem, less respect than those who don't. Same goes for vintage Jeeps, Land Cruiers and so on. Most of the members of these communities are too polite to say it though. More than likely a person who shows up at an event in a rig they purchased fully restored will get a "bless your heart"; the rig though will be admired. Those who did the work will be admired, the owner who didn't lift a finger other than to sign the check won't be.
HOWEVER - the community doesn't look down on those who do as much work as they can towards a full restoration while letting professionals do large chunks of it. It's those who don't lift a finger to do the work, they just want the "lifestyle".
Recently two individuals joined the vintage Rover world, both bought rigs that were fully restored by professionals. One couldn't even take the time to find his Rover, he paid someone to do that even. While the Landy community is cordial to this guy they absolutely despise the other. This other guy bought a Rover and paid to have it restored. He also had it modified to the point that it is now has the nickname "************ wagon".
So, yes, the cool rigs are still out there, lots of them are. Yet it's up to the buyer to decide whether he wants to take the easy way or the more difficult way.