I'm agreeing with 2octops. My Ace hardware is phenomenal.
But the best place for hardware and/or most tools has to be McMaster Carr.
www.McMaster.comI love them and use them about every week for work. Great selection. Great customer service. And the best website for a vendor that I have ever seen. It is still a wonder to me that after decades no one can even come close to their website.
But I will tell you. I too tried to duplicate Bosnian Bill's video and have spent too much money and haven't found anything that pops the key back out as well as my thumb and forefinger. I guess he was lucky with those castrating rubber bands. But I have even tried to buy those but didn't pull the trigger on them as you have to buy a huge quantity at once from my local feed store.
I say, browse McMaster Carr, find somthing else to buy, and keep using your finger for bumping.