If I were to

[jack]

Are these correct? What do they mean?
1. If I bought this, would I be able to return it?
2. If I were to buy this, would I be able to return it?

Thanks.

[Casiopea]

They're both acceptable.

1. real possibility: I might buy it. If I can return it.
2. unreal possibility: I'm not going to buy it. I am more concerned about the return policy.

[aaa]

They're both acceptable.

1. real possibility: I might buy it. If I can return it.
2. unreal possibility: I'm not going to buy it. I am more concerned about the return policy.

And what about following:
__________________________________________
We must push to work if we are to finish it in time.
__________________________________________

Why just don't say:

__________________________________________
We must push to work if we WANT to finish it in time
__________________________________________

?

Thanks in advance.