Not sure if it's an interference engine, but as for the price of that timing
belt, here's a bit I got from one Robert Ludwick, a very trustworthy
small-scale indy out in Arkansas regarding a customer's 960 sedan:
"Just in case anyone thinks that $4-500 to get a timing belt on a diesel
[240 series D24 diesel] is a daunting price, check out what they are getting
to replace a timing belt on a 960 gas burner. Most shops are charging
between $275-375 . and that job requires no special tools at all and only
takes about an hour (
I just did one on a customer car , but I couldn't charge the lady more than
$70 with a clear concience)"
He called the local dealership... they wanted $680. $250 sounds
reasonable... but if only you had a Robert Ludwick in your neighborhood. 
-Mike
