That's NOT a job for a regular DIP switch as any misconfiguration can short outputs together - either use a jumper, preferably five pin cruciform with the output from the center pin, but a 2x3 block with two commons in the middle for the output would also be reasonable, or use a four way switch, possibly a SMD slide switch.
However, you seem to be going to a lot of trouble to avoid a MCU. Any low pin count PIC or AVR with CLKOUT and a runtime selectable clock divider can do the job *WITHOUT* running the clock signal through switches.