Sears, They have 2 grades, even the better ones (Craftsman Professional, have a red twisty cap on the head)) are fairly inexpensive. You can buy them singly and get only the sizes you need.
Benchmade makes a real nice one that goes down to 6MM. I think it can be had for about $10-$12. I currently have an order going with Discount Knives. If you want, I'll add it to my order & send it in the mail to you when in. TX
I picked up a "security" torx set from a flea market in florida - hasn't given me any trouble. It goes down to extremely small sizes. If there are flea markets in your area check into it - you can get decent tools really inexpensively. If they break you just spend $2 and get another whole set.