You can't really date speaker cabs based on serial #. The speakers dates can give you an earliest possible date, but only if they are known to be original to the cab. That's tough to prove.
Between speakers and aesthetics, you should be able to get an idea of when the cab was made. Your pinstripe is most likely in the '67 era. Does it have metal handles? Or strap handles on top?
Here's a pic of a slant with unpainted baffle next to a straight with painted baffle on display in Austin. Anytime a camera flash hits the basketweave cabs the unpainted baffle really sticks out.
george