B Grade gear is considered low end now and can be purchased for adena in the Giran Luxury Shop (same wth A and older S grade); I doubt you will find players selling it anymore.
A lot has changed in Goddess, leveling is much faster now and you can reach level 80+ in about 2 weeks if you are willing to put your time in.
And 2-3 weeks if you are average player.
Not everyone is a no lifer in this game, and anyone who moves that fast certainly needs to get outside more often.
And do not edit my posts when you quote them, no lifer.
Check the auction house for gear. Sometimes the prices are very reasonable (as well as sometimes they are ridiculous). It will also depend on the server you are on. As an example, on Chronos SOP are around 10,000 for sale, and on Bartz, players are buying for 80,000.
You can just pick up C grade armor as well, which is often better.
You can easily get to A grade in a few hours now so I would recommend getting C grade to just hold you over for a few levels unless you're dead-set on getting B grade.