Also we tend to measure slings from the centre of the pouch to the finger loop.
So call it a 25 inch.
No reason you can't sell it, but 25 bucks is pretty steep for a fairly basic flat braid with a pretty skinny pouch.
Anything that someone else is willing to buy is saleable.
What you have to bear in mind is the people round here are total sling anoracks and can pretty much all make the basic types of sling.
So if you want to sell a 25 buck sling round here, it needs to either have a unique selling point, or have a bit more work to it.
Make the split pouch a little bigger and stitch some leather in there for a shepherd sling, use a couple mixed colours for a pretty pattern and you'd be nearer the slinging.org 25 buck mark
If you consider uwe sells 16 strand braided woollen slings with incredibly intricate patterns for around 70 bucks and a nice paracord and plain leather sling is around 10.
Although if you ask someone will usually just send you one for free.
You have some idea of slinging.org sling values.