There is more than enough evidence in the New Testament that proves Judas was not saved, and there very well may be even more evidence in the Old Testament. Peter had this to say about Judas:
Acts 1:20
20 For it is written in the book of Psalms,
Let his habitation be desolate, and let no man dwell therein: and
his bishoprick let another take.
Peter quoted two passages of scripture from the book of Psalms,
Psalm 69:25 and
Psalm 109:8, and he attributed them both to Judas. Here are those two bold-faced citations in their surrounding contexts:
Psalm 69:24-28
24 Pour out thine indignation upon them, and let thy wrathful anger take hold of them.
25
Let their habitation be desolate; and let none dwell in their tents.
26 For they persecute him whom thou hast smitten; and they talk to the grief of those whom thou hast wounded.
27 Add iniquity unto their iniquity: and let them not come into thy righteousness.
28 Let them be blotted out of the book of the living, and not be written with the righteous.
Psalm 109:6-20
6 Set thou a wicked man over him: and let Satan stand at his right hand.
7 When he shall be judged, let him be condemned: and let his prayer become sin.
8 Let his days be few;
and let another take his office.
9 Let his children be fatherless, and his wife a widow.
10 Let his children be continually vagabonds, and beg: let them seek their bread also out of their desolate places.
11 Let the extortioner catch all that he hath; and let the strangers spoil his labour.
12 Let there be none to extend mercy unto him: neither let there be any to favour his fatherless children.
13 Let his posterity be cut off; and in the generation following let their name be blotted out.
14 Let the iniquity of his fathers be remembered with the Lord; and let not the sin of his mother be blotted out.
15 Let them be before the Lord continually, that he may cut off the memory of them from the earth.
16 Because that he remembered not to shew mercy, but persecuted the poor and needy man, that he might even slay the broken in heart.
17 As he loved cursing, so let it come unto him: as he delighted not in blessing, so let it be far from him.
18 As he clothed himself with cursing like as with his garment, so let it come into his bowels like water, and like oil into his bones.
19 Let it be unto him as the garment which covereth him, and for a girdle wherewith he is girded continually.
20 Let this be the reward of mine adversaries from the Lord, and of them that speak evil against my soul.
That doesn't sound like somebody who was saved to me.