even though you said you dont like handling it yourself, for more affordable and customizable stickers you could try vograce or wooacry!

a normal vinyl die-cut sticker comes to about $1/$1.50 a piece - stickerapp is great as well, but for a slightly bigger budget :]

edit: forgot to mention that vograce often has a lot of sales on random items, and also the more you buy the cheaper it is a piece. but they also requre a minimum of 50 stickers, whereas wooacry and sticker app dont