99 Olds Intrigue sunroof parts

The factory sunroof on my car has broken. The slide/guide in one track is broken and the plastic "hinge" on both sides (that cause the sunroof to raise or lower) are broken. I thought it would be a simple procedure to order the parts from GM. To my great surprise, you CANNOT buy any parts for this sunroof except the plastic guides that open and close the headliner when the roof is operated. You have to buy THE ENTIRE SUNROOF, glass, wiring harness, tracks etc. Needless to say it is very expensive. The dealer wants $2000.00 to replace it. I could fix it myself if I could get the parts. Any suggestions? My car has the "shortstar" 3.5 L engine and I hear what could be wrist pin noise or piston slap? Any known issues here? The engine has about