If you have the latest design, Shelyak supply an alternative calibration lamp which can be used in place of the neon which includes Ar and other elements.(The same as used in the ALPY and LISA)
https://www.shelyak.com/produit/se0148-argon-neon-spare-bulbs/?lang=en
It has the disadvantage that there are lots of lines which can be difficult to identify so I suggest sticking to the neon and H alpha initially while we get the spectrograph up and running.
Cheers
Robin