Hmmmm... on face value I would say 'no', but obviously you would know best and in the end it's your choice, but I would keep in mind:
1) 14 may be too young to truly appreciate and care for something of such value
2) You are setting the bar quite high for future presents for your neice and other neices/nephews (you dont want to favour one more than the others)
3) You may outshine her other gifts.
If you really want to get her something Bal Perhaps get her something smaller (coin purse, clutch, shoulder) and then you can work your way up to something bigger for her 18th.
The worst thing would be that you get her a 1k+ bag and she doesnt even like it, use it, or look after it.