Those look like the same ones that I have, but I got mine from a different source. I believe it was the same source that O-Ring got them from, although I'm not sure.
I will say that they are not very difficult at all to get out if you have pressurized them. Although you are not going to do it by hand from what I have experienced, one or two turns with a crescent wrench and the pressure is released. Then you just unscrew them as normal. They are GREAT! And they did save a $70 mix for me one day, so they have paid for themselves many times over already!
Best,
TDS