My recommendation is to look at the different hoses off the shelf at the local auto parts store and make something work. I used a hose from an 88 Nissan Pulsar and cut it down for the heater return and a random double elbow from the bypass pipe to the inlet manifold plenum base. Trying to find the specific heater hoses for a Gen 1 will prove to be a challenge. Radiator hoses shouldn't be a big deal - pretty sure they share radiator hoses with same vintage vans. Don't forget the carb auto choke hoses as well (these are off the roll diameter hose you can cut to fit)