i believe the wz-88 and 89 were 14mm x 1mm left hand thread. the onyks version with the gas booster, i'm completely unsure about.
wz-96 looks like a return to the 14 x 1 thread.
you may want to drop an email to (who else?!?!) tantal at: email@example.com
he is one of the foremost tantal/beryl experts in the country.