[1.7.10] Rendering items on HUD as if they were on the floor

I'd like to render an item on the HUD using the same 3D model as when its on the floor. Currently I am using

RenderItem.renderItemIntoGUI(minecraft.fontRenderer, minecraft.getTextureManager(), inventoryContents[i], itemX, itemY);

But this only returns the same icon you get in your inventory, and in the case of items which use a custom 3D model (such as Mekanism's cables) or some more special custom 2D icons (Tinker's Construct tools) don't render properly. In the first case, a missing texture icon is displayed, and in the 2nd nothing happens.

If there is not a way to do this, is there another approach I can use? I need it to be compatible with mods that use these special methods.