http://www.oxfordadvancedlearnersdictionary.com/dictionary/opportunityWould it be correct to say "get" instead of take? (I see no problem with take, though.)
I'd like to take this opportunity to thank my colleagues for their support.
No, "get" would be incorrect there.
I have an opportunity to do something. I'm going to take it.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.
http://tfdssports.com/2011-articles/september/awards-for-the-raiders-2011-offseason.html
Moore is going to get an opportunity to make plays for the team this year.
Richelmi to deputise for Coletti - Yahoo! Eurosport
Richelmi will not get an opportunity to test before he arrives at Monza, and said that he would be treating the weekend as an opportunity to become accustomed to the GP2 car.
English riots: Britain's Got Talent dance star facing jail after looting stereo from Argos store - The Daily Record
Cowell said: "I actually was very impressed with you. I like the fact that when you get an opportunity to change your lives, you made the most of it."
Would these all be grammatically incorrect?
not a teacher
No. Your examples above my post are correct. As user Barb_D posted to get an opportunity and to take one are two different meanings.
You may get an opportunity to do something in the future. But one you have it, you take it. Or you can ignore it.
I wonder if I'll get an opportunity to talk privately with our CEO. If I do get that opportunity, I will take it. "Mr. CEO, I'd like to take this opportunity to let you hear some honest feedback from..."
The problem with your original sentence is that the personal already had the opportunity. They no longer needed to get it.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.