First I think your girth is fine, you just need to even it out so that it is equal on both sides.
Second, you can get a set of Mecate reins - 22' of a continuous length rein that can be horse hair or marine line (typically ~5/8" size). It should run about $25.00 or less if you get lucky.
The way they are setup is to have one end tied to a slobber strap on the bit and looped the length you want and attached to a slobber strap on the other side of the bit. The excess is just looped over the horn on your saddle and used to lead your horse. Training ~ Mecates
Beautiful horse btw! I'm glad you got her back.