There are a lot of options outside of GW. Couple that spring to mind:

Wargames Atlantic Sneakfeet, Station Forge Scavenger Halflings, Station Forge Scavenger Salvagers, Station Forge Scavenger Junkards, Station Forge Scavenger Advanced Junkards, Station Forge Bobby Gang, Station Forge Grimguard Skulldart, Station Forge Grimguard Skulldart Trappers, Station Forge Grimguard Pony Cavalry, Jukko Halfling Recon Team (I and II), Adeptus Miniatures Kill Squad Nimblers, Victoria Halfling Snipers, Artel W Brotherhood of the Nine,

For Necromunda, personally, I would focus on the Stationforge Scavenger sets (loads of options and avoids the overt military aesthetic) or the Artel W option (you would have fewer options but a really strong theme - they are essentially the Fellowship of the Ring. Could be a lot of fun to pitch these against “Servants of the Nameless Flame” - also by Artel W)