I always test bulbs using the slow motion video recorder in a phone. It's very effective in helping to identify flickering.
I've ordered ebay/amazon standard halogen bulbs before, and they flicker like crazy. Also some LED bulbs purchased from local stores and supermarkets.
I have a handful of really really old unused incandescent bulbs & halogen bulbs from around 2007/2008 - tested a few of them recently. Some didn't work anymore, but the one's that did, no flickering was detected.
Not sure what's changed with the halogen bulbs now, but I really wish they'd just allow the sale of standard incandescents, as they were/are practically perfect (for me). You can still source them from the deep parts of the web though.
I always look out for flicker free/low blue light led bulbs now. Mainly for my bedroom and TV room lighting. They are expensive, and (some) of them are definitely flicker free from my tests. But the color and the quality of light emitted from them is still worlds apart from the trusted incandescent.