Possible, yes. If you don't mind altering history a bit. However, beware introducing things that are used publicly. Computers, sure! You can have one in your basement/vault/secret hideout. Automobiles, no. You're going to drive it around and you need space for that. It's much harder to protect.
Back in 1950, communication on a global scale was still, well, bad. I can't source this claim, to a quantifiable degree, but there was no internet. There might be global communications for politics, industry and academics, but certainly not for the common people.
To get superior technology, without fantasy elements, you need:
- Consumable resources
- Static resources
Or more simply put, you need materials to experiment on, tools to experiment with, and scientists to do the actual research and develop the goods.
I imagine that any "elite" group of people is very, very, very rich.
So a lab and shell companies that buy a truckload of supplies more or less each month are easily set up.
But the brainpower, that's a tricky one. Academics is based on peer research. You (for the academics here, I hope I got it right) spend your life working in a field, trying to find out why something works why it does. A lot of time goes into this. You work based on the research of others - others that have researched the things you research before.
Academics is a culture based on sharing.
This contradicts the culture where an elite group secretly has superior tech.
Communication enables sharing. Thus, for this to be viable, you'll have to take away communication. This could work in 1950, but in modern times, I don't think it's viable anymore. Nearly everybody in developed countries carries a camera and a global communication device.