Guild Wars 2

Will these ever be available via laurel vendor?

Just want to know before I bother doing the achievements, as they seem quite time consuming…

That is kinda the point, and if I recall correctly you can buy more from the badge vendor once you unlock them.

You have to do the achievements to unlock the items at vendors. Some will be at the laurel vendor, but some will only be offered in Silverwastes for gold + bandit crests.