Using the other Harlequin models and some sneaky choices, here is an additional allies list using the Dark Eldar codex.
500pts (499pts) Harlequin Allies (Dark Eldar Codex)
HQ
Archon (High Warlock) – Phantasm Grenade Launcher, Blast Pistol (laspistol), Husk Blade, Shadow field – 165 pts
ELITES
Harlequin Troupe (New Harlequin models except death jester) – Troupe Master with pistol and power weapon, harlequin with pistol and close combat weapon, 2 x harlequins with kiss and pistol, 2 x harlequins with fusion pistols and close combat weapons, death jester – 184pts
TROOPS
Wyches – 4 x wyches (old harlequin models) with haywire, Hekatrix with Blast Pistol (laspistol), haywire and power weapon , Venom transport – 150