Using 4 would work I guess 
I'm having a bit of trouble finding a local source for the low speed full duplex versions but the MAX3082E seems to do what I want so I just need 4 of them then.
So if I'm getting this straight this is how I would hook this up:
For the local TX to remote RX:
Local side: DE to Vcc/+5V, DI to TX.
Remote side: RE to Vcc/+5V, RO to RX.
Local A to remote B, local B to remote A. And a resistor between A and B on both sides.
A 0.1 uF condensor between Vcc and +5V, and GND to ground obviously.