Jim Carter Antique has them
http://www.oldchevytrucks.com/cgi/htmlos.exe/start.htm
Part Number: ME148
Name: Brake Shoe Return Spring
Description: For original Huck type brakes.
Price: 7.95
How Item Sold: each
Fits: 1946-52 3/4 ton rear and 1936-52 1, 1-1/2, and 2 ton front and rear (5/8x7 inch)
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Part Number: MEW326
Name: Wheel Cylinder, New - Rear
Description: (1-1/2 inch diameter) left or right
Price: 79.00
How Item Sold: each
Fits: 1936-50 1 1/2 and 2 ton
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Part Number: ME164 ---- Chevrolet ---
Name: Master Cylinders- New
Description: New, not re-manufactured. No core charge. Mounts Horizontally Inquire about GMC
Price: 142.00
How Item Sold: each
Fits: 1938-47 Chevrolet only 3/4, 1, 1-1/2, and 2 ton (1-1/4 inch diameter
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