Some of the pelts are to show what you would wear in a colder environment - this is meant to be a 3rd Age orc of the Grey Mountains, some nameless minion. So, yes, Angband is different - but it's northerly and cold (when you come above ground), so a fur cloak would be quite useful. At least, I found it that way in bitter February winds! (mine is fake fur, though).
But yes, we should at least use the descriptions in the book as a jumping off point, I suppose
.
Here's a smattering of references to orcs from Lord of the Rings - so while we would be trying to get there in the 3rd Age, we don't have to start there. I'm leaving out the Uruk-hai, because they are obviously recently mixed with Men and have more human-like attributes than other orcs. [Is hairy ears an orc trait? A Dunlending trait? An uruk-hai trait? Or just that one guy who carried Pippin? Who knows!]
Grishnákh - "a short crook-legged creature, very broad and with long arms that hung almost to the ground." The other uruks of Mordor are described in a similar fashion. Grishnákh has "long hairy arms," a "great head," "hard cold fingers," and "a great stifling hand."
The northerners (from Moria) are described as smaller, and 'mountain-maggots'. 'Long, loping strides' are characteristic of the orcs. "Their heads were down and their tongues lolling out" when they had to run in the sunlight.
The Isengarders calling the Mordor orcs 'apes' seems to be in reference to their stature - crooked legs and long arms. Constantly calling the Moria-orcs 'maggots' could just mean that they are small and squirmy
, but could also suggest a greyish or yellowish coloring to them. Certainly, the orcs do *not* have the same skin tone as the Men of Rohan, whom they refer to as 'Whiteskins'.
In Moria, Gandalf identifies some "large and evil: black Uruks of Mordor" among the other more typical Misty Mountain orcs. I would say that this suggests the orcs of Moria are (for the most part) smaller than Mordor orcs, and also of a less-dark skin tone. It is not clear to me whether the 'huge orc-chieftain' is, therefore, a Mordor orc or a Moria orc, but for our purposes here, it doesn't really matter, as he is an orc of some sort. He is described in some detail: "almost man-high, clad in black mail from head to foot.... His broad flat face was swart, his eyes were like coals, and his tongue was red;" He has "the speed of a striking snake".
Shagrat is "a large orc with long arms that, as he ran crouching, reached to the ground." He also has "protruding fangs." Sam does say, "I've had a bit of a search to find anything small enough for the likes of us," about the orc-gear in the Tower of Cirith Ungol, so I think that even a small orc is (typically) larger than a hobbit.
"Two orcs came into view. One was clad in ragged brown and was armed with a bow of horn; it was of a small breed, black-skinned, with wide and snuffling nostrils: evidently a tracker of some kind. The other was a big fighting-orc, like those of Shagrat's company."