More squeeky rat stuff

So after my friend kindly gifted me 4 Skaven IoB sets, I decided to place the order for the rest of the stuff.  Looks like I'll be quiet for the next couple of weeks or so since I'll be busy building all my rats.  I figured I'll do rats first and then Ogres.

Anyways, here's the army now.  I dropped the Stormvermin and took Plague Monks instead.  I like Clan Pestilens stuff more anyways.  The Doomwheels because I think they're funny and double Warp Lightning Cannons because I can.  I have no idea why I took the Bell other than it looks really cool, but I have no idea how they're going to preform on the battlefield.

Anyone know where to get cheap rats for Giant Rat bases?  There's no way I'm going to buy those ridiculous GW ones.  Here's the list:

2498
12 drops

LORDS:
Lv.4 Grey Seer (Condenser) = 260
Lore of Ruin
+Screaming Bell = 200

HEROES:
Chieftain (BSB, Shield) = 72
Warlock Engineer (Brass Orb) = 65
Warlock Engineer (Doomrocket) = 45
Lv.1 Plague Priest (Flail, Scroll) = 129
+Plague Furnace = 150

CORE:
40x Clanrats (FC) = 200
+Poison Wind Mortar = 65
36x Clanrats (FC) = 182
+Poison Wind Mortar = 65
50x Skavenslaves (Musician) = 102
50x Skavenslaves (Musician) = 102
6x Giant Rats (Handler) = 23
6x Giant Rats (Handler) = 23

SPECIAL:
40x Plague Monks (FC, Plague Banner) = 335

RARE:
Doomwheel = 150
Doomwheel = 150
Warp Lightning Cannon = 90
Warp Lightning Cannon = 90