Your Regina looks to be an ORO or gold sprocket model. If the sprockets can be removed from the body (a special tool is needed to hold the freewheel body in order to reverse thread off the largest two sprockets from the back side of the freewheel), they can be polished to a high luster.

Before polishing:

After polishing:

Polishing results vary based on the sprockets, however the above example is about average.

The freewheel itself, is in my opinion, nothing special. The machine tolerances are very sloppy when compared to Suntour and Shimano freewheels of the same approximate era.

Regina freewheels were standard issue on so many bikes, especially European models, so there is value in servicing and maintaining them. While your Regina is a bit cruddy, it looks to be in otherwise good condition and should not be tossed in the bin.