Costas,
Yes, you can buy just the IMAQ Vision library. It comes with Vision Assistant, which was once called Vision Builder. The part number is 777859-03.
The data sheet indicates that it works with LabWindows/CVI and VB, which means it should work fine with VC++. If you want to be sure, download the LabWindows/CVI programming manual and see what C functions it has.
I think you will be pleasantly surprised with all the improvements since it was IMAQ CVI. That was a long time ago!!!
Bruce
Bruce Ammons
Ammons Engineering