I doubt it has been hotblued. Your barrels would probably be loose from a hot blue. Hot blueing will losen the soldered joints most of the time. You can attain a fairly shiney blue based on how fine a sanding job is done on the barrels prior to blackening. If only sanded down with 400 grit or such you will get a flatter looking finish. If you take it down to 600-800 grit you get a more richer shiny finish.
The forearm could be a replacement, but as I said it is likely similar to what it came with IMO. The shape of the tip does look a little odd to me.
