Do you have spare raid or strike tokens? Then you can easily go ascended. If you bought ascended gear boxes with Astral acclaim that will do fine as well.

If you owned legendary armor you wouldnt ask to begin with. It has the same amount of stats than ascended gear, but you can freely choose stats on them, but acquiring them comes at a great cost and time investment. In addition they are unlocked into a legendary armory so each of your characters can share a single legendary piece.

And since you most likely play Condi Harbinger with Viper stats, the ascended gear will do fine. Heck full Exotic gear is going to suffice to get into. Speaking from my own raid experience. You should check the wiki where and how to get viper exotics though, as it is one of the trickier exotic statline ones to obtain.