Xur has nothing for me again...
PSA for levelling up after PL260, these are the options, in approximate order of how much they boost your level:
Exotic quest final reward (a lot higher than your average PL)
"Powerful gear" milestones (Nightfall, Crucible, Raid, Flashpoint, a lot higher than your average PL)
Exotic quest mid-quest reward (e.g. mini-tool, drang, a bit higher than your average PL)
Nightfall end chest (separate from milestone reward, 1st time weekly only, one item will be a bit higher than your PL)
Raid Castellum chest (separate from milestone reward, 1st time weekly only, one item will be a bit higher than your average PL)
Raid Callus kill (separate from milestone reward, 1st time weekly only, one item will be a bit higher than your average PL)
Raid challenge chest (I think I got an item a bit above my PL from the special "splish-splash" chest)
Prestige NF/Raid (??? maybe an extra item once per week ???)
Clan rewards (a bit higher than your average PL)
Exotic engrams (equal to your average PL when their +5 mod is ignored, so can sometimes be better than your currently slotted gear)
Remember that mods don't affect the power level of your drops/rewards. i.e. If you purple-mod everything, you'll get +5 PL but the level of your drops/rewards won't increase.