I've just acquired a Biorad air-cooled argon laser as it was going cheap; it looks to be in good condition and very clean inside. I was hoping that it's similar enough to the Omni 543 so that I can use an Omni / Melles Griot PSU, but reading some comments from Steve regarding on of these, it seems that that isn't the case.
I've trawled ebay for a PSU, but they don't seem to be particulalry common; hoping someone may have one they're willing to part with or suggestions as how I could power it with something else - I have a collection of Omni / Melles 170 PSUs and a very old Omnichrome 150 (no suffix) PSU in the collection.