Want to upgrade forks to cartridge with full adjustability. SP forks are rare here in North America, and seem pricey from Japan. So how about CBR600 F2 (late) or F3 forks? They are 41 mm with cartridge design and adjustability, common and inexpensive. Anyone tried fitting these?

BTW club rules prevent use of upside down forks.

VFR400 forks (NC 32?) forks would be an option but do they have rebound adjustment?