There's always this one.

http://www.bhjdynamics.com/index.php?main_page=product_info&cPath=1_2_35&products_id=39

Kinda pricey, makes the $150 rebuild of the stock damper look cheap.

FWIW, I have no affiliation with BHJ or any of their dealer network.

My, what a steep learning curve. Erik II#5155