Thanks for the comments all!
Great work on the undead Pil. Did you put the same design on the hierotitans clothing as on the necromancer? Really like how this set turned out, great job! Btw, also liked the orange one most myself 
The patterns are not identical, the colours of the clothing is also a bit different, with the Necromancer's robes being based on Citadel Foundation Dheneb Stone and the Hierotitan's robes based on VMC Khaki, the end result is rather similar though. The Necromancer has a greenish simple meander border like the second one from the bottom in this example:

The titan has a more complex meander with swastika's in them in black. You can see an example if you click this link, as I'm not too sure whether or not it's allowed to post the picture here:
http://www.pitt.edu/~medart/image/glossary/Greekkey.JPGAs for the model, I'm 99% certain it's an old Grenadier model. Mirliton doesn't seem to stock it but it looks like their "Half Giant Liche Lord" was based on the same model:
http://www.mirliton.it/product_info.php?pName=half-giant-liche-lord&cName=fantasy-2528mm-undeadIt's a rather nice model which I picked up cheaply on eBay and doesn't seem to go for very much there, but it's not really common either. He's also rather flat but that doesn't show in the pictures and he makes a nice Hierotitan for Warhammer 8th edition Tomb Kings armies
