A close friend bought me a bullet once and I didn't find it weird at all. We talk about sex all the time and don't hold back, so if your friendship's like that then I think it would be quite a nice and girly gift to give them. And chances are no one else will buy them the same thing :p
If you go for it, I'd go for the pin up one!
A female friend told me she didn't know where to start introducing her OH to something different in the bedroom, so I bought her the LH beginners sex toy kit and the Tracy Cox bondage tape. A male friend is very adventurous but going through an especially dry spell, so bought him a toy to cheer him up. He's returned the favour buying me a vibrator and some nice lingerie, which my OH definitely approves of.
Basically, having been on both the giving and receiving end of sex toys with friends, I don't see a problem. My general rule of thumb would be that if you know them well enough to know what sort of thing they'd like, then there's not going to be anything weird about you getting it for them.
And as a final note, have just bought the pin-ups set for a friend - thanks for the idea!