You should be able to get them from any chemist, you might have to ask at the counter as they are often kept behind there to prevent theft. You can also get them from your local walk in centre. If you have some medical tape, you might be as well making your own till you can get them.
How to make butterfly stitches

Butterfly bandages are best for closing a long cut.Use an adhesive strip (such as Band-Aid) to provide continuous pressure. Always put an adhesive strip across a cut rather than lengthwise. A butterfly bandage (made at home or purchased) can help hold cut skin edges together:
Using a clean scissors, cut a strip from a roll of 1-inch adhesive tape and fold it sticky side out. Cut notches into the tape as shown in illustration A above.
Unfold the tape; then fold the notched pieces together, sticky side in as in illustration B above. The center of the tape will not be sticky. Keep the part that will be over the cut clean.
Place one end of the tape on the skin. Then pull the other end to close the wound tightly as in illustration C above.
If the cut is long, use more than one bandage.
Apply a clean bandage at least once a day, or when the old bandage gets wet or dirty.