The socks on the Reign Pant are the exact same as the socks on our drysuit. The socks are made out of the same waterproof breathable material (eXhaust 3.0) that the pants are made out of. The socks also include a cordura panel under the foot for extra durability. We still recommend wearing a bootie over top of them for extra protection though.
The socks are sewn on permanently but in the past we have had people send our drysuits to repair shops and the repair shop has cut off the bootie and attached a latex gasket to it. So if you are really keen on the gasket you could always check at a repair shop to see if they could do it for you. I recommend Rainy Pass (Rainy Pass Repair, Inc. Gear Repair
As far as the extra tall waist band goes, I am a true believer in it when it comes to dry pants with booties attached. Anything you can do to help keep the water out is well worth it. I found, when prototyping the pant that I did not notice the extra tall waist band at all. It is made out of a very high quality extra stretchy neoprene so it flexes very easily against your body.
I hope this helps.