it's looking very likely to be from some block called rodger for the usa, 3 way adjustible. been asking a local tuner down here who has set the suspention up a few sucsesful Targa cars, and he recomended Penske and Ohlins over MCA. Because the Penske and Ohlins engeneers will valve to the specs you ask for, and Murry does what he wants. The shocks them selvs are much of a muchnes, appart from the Penske and Ohlens being lighter than the MCA (aloy vs steel).
Ohlins is way too dear, and if the valving needs to be modified i've got somone here who can say the valving needs to be changed to be xyz, i need somone who will try to get al close to xyz as possible.