Cap for 155 anthem cup?



I've been using the siphon cup that came with my Anthem does anyone know if they sell a cap for it or is their a diy alternative? Thank you in advance and have a great day.
Aluminium foil and a rubber band then just poke a small hole in it with a needle. Some other brands do fit but cant remember which off the top of my head, or use another brands one upside down again with a rubber band to hold it in place.. and I think ya can also buy the plastic throw away type on Ebay (Just measure the ID and make sure what ya buy has the same) or find sumfin else around home to do the job..Good luck..You have a great day too :)
Rebel & Son thank you for the info it is greatly appreciated.