There is a sizing chart right below the drop down menu, which tells you the lengths of Mountain Hardwear clothing. You will probably need a Long pant, but bc.com is apparently out of stock at the moment.

They are made with a softshell material... so they will be more quiet than shell pants... but, not as quiet as say a cotton pant. You'll probably hear a little swish but I would bet that it won't be to bad. Hope this helps.

These are typical all-round cold weather softshells, I live in Northern Norway. Foul weather, whiteouts and zero visibility snowstorms is the most common weather desember through february.
I would use these pants for anything, just keep in mind that they aren't bibs and they don't have internal gaiters, I use my patagonia super guides for big mountain and deep powder, the Makalus are more comfortable so I wear them whenever it's not deep powder or sleeting sideways.
Paired with gaiters you'd have the full package tho.

True to size, tho I feel the thighs are a bit baggy.

They run true to size.

Check out the Mountain Hardwear Navigation Pant for a softshell pant that comes in a long. I don't see them on the site... but, still. They are great pants.

I own both these pants and the fabric of the Makalu is alot like Polartec Powershield Lightweight (which is a good thing) So it compares more to the Gamma MX, or somewhere in between the AR and MX. It's extremely soft and comfortable, like wearing sweatpants.

I think that the Makalu Pants are a little heavier in weigh than the Gamma AR Pants. The Makalu Pants have a brushed interior that feels really soft and fleecy. Not sure about the Gamma AR Pants. The Makalu Pants weigh 19oz. and the Gamma AR's weigh 17oz. and both I am sure are very durable. Here is a description of the fabric used in the Makalu Pants - Tuff Stretch Thermal: 58% nylon, 31% polyester, 11% elastane four-way comfort stretch double weave, 168 x 153. Durable, tightly woven nylon face with soft brushed back. DWR finish. 7.25 oz/sq yd. Hope this info helps!