I was under the impression that a common blacksmith would not find making bullets particularly difficult so a settlement of any size likely has a good supply, especially of common rounds like 9mm and whatever AK-47's use.

There should be plenty of sources of metal (rusted cars etc) to be melted down even without mines, and as there is a town militia with guns and we all have guns I find it unlikely that bullets could be that rare.

My intention was for the price to be way over the top but if we are thinking bullets are very rare I'm happy to change it.

edit: 
We just made posts at about the same time so I'll just reply here?

My intention is to have been scammed out of a few bullets and the price being too high, so like I have 30 bullets not 52 and I payed way to much for what I've bought (even if I had 52 bullets).

How rare are bullets? 
I see how people not in settlements would find it hard to make them etc but in a permanent settlement? 
If they are indeed rare then thats fine ofcourse, I will change my post to buy fewer bullets :P