I myself needed something better. Inspired by a hungarian horse archer master, I designed myself a new, high capacity hip quiver from proper leather.
It works remarkably well and I am quite happy with the results. It can hold a large amount of larp arrows(currently loaded with 15 but there is room for more) which suits me perfectly. Loaded with normal arrows it could probably hold almost 100 max.
TOOLS & MATERIALS
Alas, making it won't be possible with just duct tape, good will and whatever you found in the attic.
I used 4mm moderately hard leather and I recommend the same. Its expensive BUT if there is a leather workshop nearby you can buy leftovers and then combine them into big pieces like I did.
You will also need something to cut the leather good, a simple home scissors will break/blunt itself, although you can, if you combine it with a sharp knife. Rivets or very strong thread is necessary too. Hole punchers for the leather - either hand punch or hammer punches, whatever you can find. I have a hand punch and I decided on rivets for extra durability.
KEY DESIGN POINTS
The top of the quiver has to be wide. That's where the belt passes through and since its a wide connection, you don't have to tie it to your hip - it stays put while you move around.
The quiver itself must be flat, and roughly 60-70 sm long. Mine is 67sm long. You can make it as wide and with as many arrow slits as it fits you.
Since the quiver is flat, the arrows have a hard time falling out. Its not impossible, but gravity alone is not enough. Here I am holding it upside down with no effect. Needs a good shake up for them to start dropping.