There is a cashier position in a local supermarket, but they've said that for the moment they have no male uniforms and that I should try again in the future! The uniform is in my opinion fairly unisex; trousers as opposed to a skirt, plain blouse (which looks like a shirt) and a cardigan. I have no problem wearing this uniform and need the job. I'm fairly slight of build, so don't think sizing should be a problem. How do I stand on this?
This is a borderline legal issue. In the US, you can not be turned down for a job based on your sex. They are turning you down because you are a male. Not having a male uniform is their issue, not yours. In my opinion, that sounds like sex discrimination.
You should consult a lawyer in your jurisdiction, if you feel the position is worth fighting for. However, lawyers/courts do cost money and there is no guarantee of a positive outcome. And do you really want to work at a place you took to court?