I've been buying 60lb pails of honey from Webstaurant Store for a few years now, going with Monarch's Choice Orange Blossom or Wildflower.
Not sure if you'd win awards using it, but it works well if you want to jam out some hydromel for casual drinking or if you need a template for ingredient trials.
I see you're in the Bay Area. By coincidence I just started a trial batch of canola honey mead yesterday that I sourced from Mike and Nickey's Honey company. To be clear: the jury's still out as to how this is going to go, but they had a solid selection and were willing to engage to when I queried them about it. They also have blends from the local area which I want to play around with in the future. Not sure they can do 5 gallons, though, you might have to stack a few 1-gal jugs.
Lastly: USDA Grade A means it is actual honey. To be clear: I'm not arguing against raising an eyebrow at Sam's Club, and I understand that labels aren't the be all and end all of what's actually in the bottle, but filtered, not raw honey is still, objectively, "real" honey. Assuming it's not counterfeit, the only thing they've done is filter out pollen and bee parts.