Personally i think you should make it about him as a person rather than 'he is from back home therefore i do not want to marry him' say to your mum he is not educated (apart from the course and metric lol) and also how much does he really make in the general store....its about him being able to provide for you (dont beat me girls)
if you feel you really do not want to marry him and also you want your parents to feel you ave listened to them i say meet the guy give him the benefit of the doubt and then say 'mum i dont like him for because.....xyz' and then go from there...:)
Phil, is he a relative? If so then maybe your parents feel a sense of security...and that perhaps it will be easier to trust him.
However, obviously with you having been raised abroad and him back home, there will be cultural gaps, not to mention that he doesn't seem to have the potential to earn a decent living right away. But if he's bright and ambitious, he could come here and work up his way to a stable career.
What I would suggest is:
1. Allow yourself to look at him after telling your parents that you will do so with an open mind.
2. Open your mind and heart, and really talk to him to get some vibes.
3. If you cannot connect, apologize to your parents and move on.
Parents are pressuring you but they will never force you if you are not satisfied.
Just talk to him and see if he can be the guy you can settle for and if he doesn't have those qualities tell your parents why and move on. Your parents might not really like it in the beginning but they will be all over the next rishta that comes along and forget about this one.