A lot of kids collect these badges. Sending requests like that to small clubs is common enough as smaller clubs are more likely to respond favourably. Does your club have an internet presence that they've found? Perhaps your club is listed on some pin-collector websites these people are getting their contacts from?
If they wanted to make up the badges, they wouldn't need to get a physical one to do so, just an image. Anyone interested in selling knock-off badges is only going to go for the high-volume sellers like Barcelona, ManU, etc.
Leo