level shifting options
Below please find High-rel level shifter circuit. This should work fine at the baud rate you mentioned. Select R3 based on acceptable rise times. Since I am not sure what incantations or rituals are required to create Hi-Rel components, I leave the selection of U1 to you. Hopefully you will also be able to source Hi-Rel resistors for R1, R2 and R3. You will also need a 0.1uF bypass cap.