HARKEN HC7798 (with 57 Black Magic blocks) - listed new on the internet for just under $700!!
Sheave Ø (mm) 57 mm
Sheave Ø (in) 2 1/4 in
Maximum line Ø (mm) 12 mm
Maximum line Ø (in) 7/16 in
Maximum working load (kg) 2200 kg
Maximum working load (lb) 4850 lb
Black Magic Air blocks - lightweight, free-running and powerful. Blocks feature a center cage that contains the Torlon® roller
bearings separated and parallel to reduce friction.
https://www.harken.com/en/shop/black-magic-air-blocks/57-mm-aluminum-block-german-admirals-mainsheet-system/