Copper crush washers can be annealed and re-used without leaks until they are mechanically damaged. It's really simple to anneal them also. Sting them up on stainless steel safety wire, heat them until they are cherry red, quench in cool water or just air cool. If you only doing a couple this will probably cost more than new replacements though.
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Manteca Mazda Asylum
where a boy and his cat live, without adult supervision