I sadly don't have any kislev warbands to sell you, but come bearing this suggestion: Loot any and all other miniature lines you can get your hands on.
The Horse Archer upper bodies works perfectly with Empire Militia legs. The kossars and boyar has your hero repertoire pretty much covered. I don't have any especially nifty suggestions for tamers at this time, but I've always been a fan of this direbear from Reaper:
Anyone else know of any fitting Kislev-subtitutions available out there? Some of Perry Miniatures' Choson Koreans might work if you greenstuff some fu manchu mustaches on there. Many of the Crusade-era muslims could work too.. unfortunately most of them are on horseback. The notable excepiton would be the Azerbaijani swordsmen:
I'm thinking those shields are probably integrated though. Shame!
Best of luck with your hunt, and be sure to show 'em off when they're closing in on being table-ready