Assistance needed - Detroit Lubricator

I'd like to repair this 1890's, pint size, dual feed Detroit Lubricator however the fitting on the lower right does not appear to be correct.

Does anyone have any early Detroit Lubricator catalog that depicts this configuration?

I think I need to replace the fitting on the right so it matches that on the lower left but with a drain cock. I've looked at a number of old lubricators, for parts, but haven't found anything appropriate. The left side fitting measures 7/8 high by 1-5/16 square.

The left side glass tube is easily removed through the lower fitting by first removing valve stem. The right side glass tube is quite sloppy and can only be installed or removed by turning the side fittings.

Any help is greatly appreciated.