Tandem stoker stem or stem for the rear rider. Then add a pair of 25.4mm handlebars and you are away.
TANDEM STOKER HANDLEBAR ALLOY STEMS 25.4mm H/BAR 27 / 27.2mm POST 20+80mm REACH
2Pcs Bike Mirrors 360° Rotatable Rear View Handlebar for MTB & Road Cycling UK
Hafny HF-MR081 Fully Adjustable Magic Bike Rear View Handlebar Mirror - Left
BICYCLE MIRROR BIKE SAFETY REAR VIEW Handlebar Plastic 360°Rotate UNIVERSAL 1PC
