Avery offers Custom Shapes on sheets. If you're looking to order for individual Custom Stickers, you can do so here: Custom Shaped Stickers.
To order a Custom Shaped label on a sheet:
1) Go to the custom sheet labels calculator page
2) Use the Shape drop down and select Custom Shape
3) Select your size or type in manually
4) Scroll down and select the Material and Quantity
5) Select Upload Artwork
6) In the Custom shape window, review and keep as is or for a close cut select Contour Cut
7) Select Finish then Add to Cart