If that covers the cost of materials, and you did it as a 'practice', then I think I would be happy with that .... and presumably as you've had it a while yourself (I didn't get the impression that it was 'just finished') you have written off your costs anyway ... you were not expecting to get the costs back on this item.
In that case I would be happy to sell it to her for the cost of the materials, and treat yourself to some new materials with the money - and tell her this!
... but also to make it very clear that you are selling it to her for the cost of the materials alone, and that if anyone else wanted something similar the price would include your time ... and would therefore be at least double that.
So - Yes! - for a good friend who likes my practice effort that I no longer like much myself ... I think covering the cost of materials is fair.
Helen