bad seat-belt, w210, 2002 e-wagon

[Paul T]

The kids were playing with the passenger front seat belt. Now it will not come out. It is fully retracted, but there is a little slack, perhaps 2" slack, enough to let it retract, but when you pull on it, you get an inch or two of outbound travel, and then the pawls grab, as if the belt were pulled out rapidly.
The part is $200 to $300, plus opening up the interior column. Any thoughts?

My other car is a 1995 E320 wagon w/ over 200k miles.