I just purchased some abec 11 90mm 75a genuine flywheels on Amazon, i believe the seller has another 17 sets in stock at about $ 88 a set. Below are links. MuirSkate.com also has 83mm 75a genuines in stock as well as 90mm 75a’s if anyone is interested.
90 mm 75a genuine flywheels on amazon https://www.amazon.com/gp/offer-listing/B002UZP0EO/ref=dp_olp_new_mbc?ie=UTF8&condition=new
90 mm 75a on Muirskate.com - sold out
https://www.muirskate.com/longboard/wheels/1874/90mm-abec-11-flywheels-downhill-longboard-wheels
83 mm 75a on Muirskate.com https://www.muirskate.com/longboard/wheels/1314/83mm-abec-11-flywheels-downhill-longboard-wheels