Try a local Hydraulic Servce/Repair shop.
They have an extensive selection of the 37 Degree fittings,
as they are used in Hydraulic Pressure applications.
Between the normal Aviation sources, Farm and local Hydraulic shop
I found everything I needed.
I just bought a tee with a swivel on the run from Pegasus Auto Racing. They show a 45 degree one on their website. I was totally satisfied and received the part within days. I needed the tee to adapt an Andair valve to the High Pressure Fuel Pump.
