If you have trouble getting suitable birch bark, a number of the quivers remains from the circa 8th century burials of Moshcheveya Balka were leather covered. These were generally of D-shaped cross-section with a flat back. They were made from thin wooden strips with a covering of leather or birch bark and a fairly thick wooden base. Some had bone pieces for decorative reinforcement. One variant had a wooden board for the back.
Below is a photo of a simple quiver I made last year, very loosely based on the these finds. Other than the carved base plate design, I don't make any claims to it's historical accuracy. It was made with a wooden back plate and a leather front, and was quite simple to construct. It seems quite rigid enough without the wooden strips.
Quivers at the site came in a variety of sizes, with base widths of 10 to 18cm (4-7 inches). Mine is about 13cm (5 inches) across the base and holds a dozen arrows comfortably. The interior length should be a bit longer than your arrow. The shaped opening at the top guides your hand down below the arrow tip to avoid stabbing yourself.
The Moshcheveya Balka burial site is in the territory of the Alans, at the time they were part of the Khazar empire.
Last updated on 02 April, 2006