Gearing and chain setup for custom with 17” rear

[AshishNJ]

The build has 81 motor and is fitted with Ducati 916 swingarm and carries 17” wheel. The rear Ducati sprocket has 38 teeth but I do not have a chain and front sprocket yet. I am wondering what type of front sprocket I could use ( assuming Ducati had 530 chain setup ) and what front tooth setup would bring the motor to a close to stock rpm and ground speed.