Zombie survivor figure suggestions.

[Brummie Thug]

Rogue Miniatures though themed on various 'Not' figures has plenty of lightly armed characters. RedRum,  Only One, The Disguise and The Daddy all have melee weapons as well as there being suited pistol wielders.
http://www.rogueminiatures.co.uk/index.php/gun-miniatures.html

Crooked Dice have various civilian characters that could be converted. The Man from 3000 comes unarmed but has a revolver on his base tab. William Killian would look great with a crowbar added. Theres Misty the zombie hunter with her hockey stick.
http://www.crooked-dice.co.uk/wp/product-category/miniatures/

Copplestone Castings KKBB has plenty of people with just pistols yes a lot of people are wearing suits and such but the KGB and Agent sets will supply pistol armed folk. Some of the henchmen that have no weapons could have melee weapons added to them from your bitz box.
http://www.copplestonecastings.co.uk/range.php?range=KKB

Copplestone Castings also has various packs in the Future Wars range where you'll find variously armed folk. Men in Black, both Corporate babes packs. Some of the Babes with guns could work as well.
http://www.copplestonecastings.co.uk/range.php?range=FW

EM4 similar to Copplestone being the same sculptor plenty of figs in there across the range.
http://www.em4miniatures.com/acatalog/Future_Skirmish.html

Already mentioned various Hasslefree including there juvenile figs, RAFM Modern USX, The WGF sets.

Offensive miniature rioters sets have a lot of close combat and improvised weapons
http://www.offensiveminiatures.com/catalogue.asp?RID=7&CID=3

Theres plenty of other ranges you just need to explore a bit and use your imagination. I have some Rachel Knight from WarmAcre Games converted up as a survivor even though she is in commando fatigues. Paint the clothing different and its someone in hiking gear.
http://brummieswargamingblog.blogspot.co.uk/search/label/Warm%20Acre