Good to hear from you Ricky!
First off- no way we get Davis. Kid is a stud and will dominate the league for years.
Secondly- Rondo- in your scenario he stays around and he's the "PP" cornerstone of the franchise that we pair two other stars with. Unfortunately, I don't think Rondo is the guy you build around. For the sake of the hypothetical though I will include Rondo.
Now, as for the "steal" guys (Ray)- Players like OJ Mayo, Demar DeRozan, Monta Ellis, fit the bill and all of them have more left in the tank than Ray did when we acquired him. While Toronto is on the rise, I could still see Demar leaving for "greener" pastures. Mayo and Ellis could be acquired cheaply I believe.
Now for KG- (also a steal IMO

The only player I can think of that could potentially be acquired and is of a similar caliber to KG is Dirk. Clearly he's getting towards the twilight years of his career, but I think he could easily hold his own on a contender for another season or two. If Al Horford wasn't so injury prone I would probably select him.
Other PF's I can think of are Millsap and Faried. I believe both are attainable and while they are "second tier" power forwards they certainly have the talent to score (Millsap) and defend (Faried)
Now I'm gonna go a step further for fun and replace other members of the 07' squad.
Perkins- Gortat- the guy straight up looks like Zangief from Street Fighter. He's perfect.
Posey- bring in Trevor Ariza. Love this kid even though he killed us in the finals with L.A.
House- Ben Gordon. Dude can flat out shoot. Would be great off the bench.
Cassell- Andre Miller. Dust him off and let him mentor Rondo.
PJ- Bring in Camby!
What do you think?