kardashiandisick091311_01_X17230WM.jpgScott Disick has bought longtime girlfriend and baby mama Kourtney Kardashian an engagement ring, according to Life & Style.

Mason's daddy reportedly has been holding on to the ring since he purchased it back in September at Classics Jewelry in New York. An insider dishes to the mag, "He chose a 1.5-carat princess-cut-diamond ring."

Fans of Kourtney & Kim Take New York may recall that Scott purchased a ring for Kourt last year, as well (but returned it) ... after planning to propose to her during last season's finale episode. Perhaps this time around, he'll follow through with his proposal plans.

The friend of the couple adds:

    “Right now, they’re so in love and so happy with each other and their family that there’s no reason for them not to get married. Kourtney has also really come around to the idea of marriage.”

Kris Jenner better get ready to plan yet another Kardashian event!