1986 Trooper Accelerator Pump Piston Leaks

Looking for a source of a rebuild kit (or part) to cure the problem. It seems as though the little O-rings on the piston are shot...at least thats all I can think of without disassembly.

It started after leaving the beast sitting idle for about two months so I guess they dried out. Carb was rebuilt about 10 years ago but I don't know if any of this was replaced back then.

Any pointers?

TIA,
Bill

Try NAPA or St Charles Isuzu.

Thanks. NAPA is a no-go and I was holding back on calling St. Charles Isuzu until I looked at other options. I might just wind up buying an assorted selection at McMaster-Carr hoping to hit on one that fits. Budget Crisis, ya know.
:)