No, they are not. You spend at least 2 hours on each of them and the thread costs something too, so lets say from a 6.00 price, 2.00 goes on materials (and getting to the shop to buy them etc) and then you get 2.00 for the work per hour. That is definitely not even the lowest wages you would take a part time job for...
The work is fiddly and you desere to be paid for it properly... do not fear to rise the prices a bit, it wont hurt...