Choke tubes for old model Ithaca 37

[ratltrap]

Has anyone had choke tubes installed in an old model Ithaca 37 barrel?

I have a 37 with the old hand fitted 30" full fixed choke barrel. I used it quite a bit for waterfowl before steel was mandated, but now find it pretty useless for that and for upland hunts as well. I've heard that it may be possible to fit those barrels for choke tubes. If anyone here has done that for one of these I'd like to hear about where they had it done and how it worked out.