Call KBI, SOG, and Numrich. Parts for obscure guns without large sales volumes often don't make it to the web listings.
They were cheap but good guns when new, personally I'd shoot it and not worry about it. If/when it breaks, sell whats left to Numrich if they don't have the part you need and buy something else.
The only guns with really good spare parts availbility are guns adopted by the military or multiple large police departments.
--wally.