It depends what you are looking for and what you're willing to give for it, if it's something not too obscure and it's a fair enough offer then it should work just fine, I've had stuff come to me without wanted ads just purely where it's come up in conversation so give it a go if theres something you want but also search at the same time to increase your chances.
You'll Shoot your eye out Kid
Currently looking for an SMK/BAM B4-4 Rear sight or help modifying current one.
Wanted Daisy Model 25 or Norica Commando in reasonable condition.