I don't have one of those, but have several of the smaller versions, in both CF and pinfire. I doubt you will find any parts anywhere for that gun. The springs will be mostly forged V springs with some forged flat springs. They can be made and fitted by any competent gunsmith, but if several are needed I can almost guarantee that the cost will exceed the value of the gun, assuming the $500 figure is about right for yours (and it seems right for the gun being sold).
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