Beeman QB chief.

I can pick one up pretty cheap at 165 new. I have read about parts being hard to find. My question is that due to the times and many things being in short supply or is this going to be a forever thing? I see they released a newer synthetic version so I don’t understand how parts for these guns will never be available again?? The other pcp rifles in this price category seem unavailable now. So should this model be forever avoided? Is it so bad I wouldn’t even be able to get a seal? 
 


https://www.archerairguns.com/QB78-Valve-Stem-p/qb78stem.htm

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http://mountainaircustomairguns.com/faq/

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