Hobart Spool gun DP-3035-10
Can you take a picture of the leads and how many holes in the twist lock plug?
I dont recognize the set up for a Miller as they are a 14 pin amphenol style plug for a direct fit connection.
A direct fit for Miller into a 210 is typically a 4 wire plug.
I'm thinking only a Hobart Machine will work. The more details the easier it is to sell ( or buy).
Good luck.