The difference between the Gospel and the Holy Bible.
The Injeel as Islam describes it has no evidence of existence outside Islamic sources, nor do Jesus' Muslim followers. The early Christians never believed that Jesus was given the Gospel from God like a prophet would be given. But rather he gave the gospel to his followers and it was his followers who eventually recorded it.
And we afterwards continually remind each other of these things. And the wealthy among us help the needy; and we always keep together; and for all things wherewith we are supplied, we bless the Maker of all through His Son Jesus Christ, and through the Holy Ghost. And on the day called Sunday, all who live in cities or in the country gather together to one place, and the memoirs of the apostles or the writings of the prophets are read, as long as time permits; then, when the reader has ceased, the president verbally instructs, and exhorts to the imitation of these good things. The First Apology (153-155 A.D) (Emphasis Mine)
Notice Justin Martyr never mentions one Injeel given to Jesus, like the one described in Sura 57:27. But rather a collection of documents written by his disciples.
Also, does anyone have the original version of it (I mean the original version which was supplied by Jesus Christ, peace be upon him)?
No one has the gospel described in the Quran, no one has evidence of the Muslim followers of Jesus either.
"The Gospel" is a phrase used to describe either some books in the new testament (Mathew, Mark, Luke & John) and/or the general message of Christianity.