Here is a switchable magnetic grow light ballast designed for 1000w S52 high pressure sodium lamps and 1000w M47 probe start metal halide lamps:
https://www.ebay.com/itm/154469096579?hash=item23f7135c83:g:RZcAAOSwGidgruOvOn this ballast, it is safe to run 1000w H36 mercury vapor lamps, but not 1000w H34 mercury vapor lamps.
The 1000w switchable ballasts are more common than the 400w switchable ballasts.
When you use mercury vapor lamps on these ballasts, it is important to have the switch set to the "metal halide" setting since that setting has the ballast's ignitor disconnected. You can run the 1000w M141 pulse start metal halide lamps on the "high pressure sodium" setting since those lamps need an ignitor to fire them up. Lastly, the Philips CDM 860w AllStart ceramic metal halide lamps can be used on any setting.