Hi Gruby
The frameset in the pics is definitely a Colnago, probably dating from somewhere in the '90's. It has the Gilco crimped tubing and the fancy headtube lugs.
I think it has been resprayed, possibly because the original paint work was damaged/rusted beyond just touching up.
This would explain why the fork is a non Colnago fork.
It would have been more expensive to re-chrome the original fork than to buy a cheap replica.
Another reason to replace the fork would be if the original had been damaged in a front end collision.
Heavy front end crashes result in damage to the top tube and down tube which is usually visible, but lesser collisions sometimes don't show as much.
At the end of the day, this is a Colnago frame from in my opinion the best era of steel bikes. If it's straight and true you could have a great ride.
There's a thread at the top of this Retro Classic Road forum for what's a bike worth. Put a post in there.