This one might work:

FB-4000 Information

These folks probably also have one that will work, but they may be a little pricey...

Bellow Seal Boots by Gardan Manufacturing Company

__________________
Respectfully,
/s/
M. Dillon
'87 124.193 (300TD) "White Whale", ~392k miles, 3.5l IP fitted
'95 124.131 (E300) "Sapphire", 380k miles
'73 Balboa 20 "Sanctification"
Charleston SC