Answer
Wa `alaykum As-Salamu waRahmatullahi wa Barakatuh.
In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
There is no sin on you if you go for Hajj with the money that has been given to you by one who is known to earn interest-based money (riba).
Elaborating more on this issue, the late prominent Saud scholar Sheikh Ibn Uthaymeen (may Allah have mercy on him), states:
If a person is given some charity by someone who earns interest-based money, there is nothing wrong with him using that money to go for Hajj.
There is no sin on him if he accepts what is given to him, because the sin of interest is borne by the one who engages in it.
As for the one who takes it in a manner that is approved of in the Shari`ah, such as by being given it as a gift or a charity, there is no sin on him.
The evidence for that is the fact that the Messenger (peace and blessings be upon him) accepted gifts from the Jews, and he ate the food of the Jews, and bought from the Jews, even though the Jews are known for earning interest and consuming haram wealth.
If we assume that someone steals a sheep from a man’s flock and comes and gives it to you, then in that case it is haram, because you know that this sheep does not belong to him.
But if he was earning interest, then his sin is on himself, and whoever takes it from him in a manner that is approved of in the Shar`ah, it is permissible for him.
Allah Almighty knows best.
Source: www.islamqa.info