I'm one of the guys that had to replace my Besko loader valve because I lost a $.69 spring for the one of the spools. Tried to contact Besko directly, but that was futile. Didn't even get a "go-to-hell" back from them. Also contacted 5 different dealers, and nobody carried any parts (gee...there's a surprise)
Ended up buying a new replacement valve assembly from Surplus Center. Pretty happy with the replacement. People there are very helpful too if you need some advice.
Here's a link if you want to check them out:
Hydraulic Valves,Directional Control Valves,Log Splitter Valves,Joystick Valves,Solenoid Valves,Sectional Control Valves,Pilot Operated,Power Steering
www.surpluscenter.com