You can measure the pan and figure out the cubic inches, then use an on line converter to tell you the volume for fluid, but the stock dip stick is probably going to be pretty close.  Many of the production after market pans are just converted from stock pans.  Do you know if there's a wind-age tray in the pan?  I measure for oil level by filling the pan to the windage tray and mark my stick there.  If this isn't a race motor, or something you plan on turning a bunch of RPM with, I wouldn't worry about running the oil level low to pick up extra HP.  Just by looks, I would think 10 qts is going to be pretty close, including the filter.  Maybe put in 8qts, prime the engine to fill the motor and check the stick.