slug barrel for ithaca model 37

[MiG25]

does anyone know what would be involved in fitting a rifled barrel to an older ithaca model 37? from what i have read, the ones below SN 855000 need to have the barrel fitted by a gunsmith.

anyone know who in calgary or edmonton could do this? is it a matter of having a model 37 or 87 rifled barrel fitted?

thanks and regards.