Who knows SC heater hose specs?
 

I want to change out all of my heater related hoses and source my own stuff.

I think there are something like 6 hoses (5 round, 1 molded) in there.

Exchanger to flapper, right (high heat requirement)
Exchanger to flapper, left (high heat requirement)
blower to reducer, right (cold air)
reducer to exchanger, right (cold air)
blower to exchanger, left (cold air)
fresh air to blower (cold air, this is the molded plastic part)

Are all the round the same diameter? What are the various lengths and if not what are the various diameters?

Can the molded hose be replaced with something round that's not super expensive?

I was thinking about replacing my hoses also, those light brown ones are terrible on the eyes. I'm curious to see how your project turns out.