I've ordered blades from RBC. It's a great site for sampling blades (5 packs). However, since covid, my order last year took over a month to make it to the USA. If 7'oclock yellow isn't doing the job, have you tried Feathers? My son-in-law has only ever used Feather blades and won't use anything else.
As for me, both yellow and feather are too sharp for my old mug. I needed a sharp, but forgiving blade. Astra and SP were fine when I shaved every other day, but shaving less frequently, I needed a sharper, forgiving blade. I settled on Gillette Platinums. That's where blades really get really confusing, as there has to be 3-4 variations, Platinum laser, ink, new and a Bullgoose version in a dark blue box which I prefer. I've tried most, including GSB, but prefer the Bullgoose blades. I can't link to that one, because the site is closed until next year.
As for me, both yellow and feather are too sharp for my old mug. I needed a sharp, but forgiving blade. Astra and SP were fine when I shaved every other day, but shaving less frequently, I needed a sharper, forgiving blade. I settled on Gillette Platinums. That's where blades really get really confusing, as there has to be 3-4 variations, Platinum laser, ink, new and a Bullgoose version in a dark blue box which I prefer. I've tried most, including GSB, but prefer the Bullgoose blades. I can't link to that one, because the site is closed until next year.