My help here will be dated and so not terribly helpful
I built kits years ago and got them through Shotgun News ads and I think they came from EMF. I have not read a Shotgun news in a long time. At the time I was building revolver kits, they had the best deals by far. That was pre-Internet. By and large the action was ready to go and the work on the revolver involved only finishing.
I built a CVA Kentucky Rifle and it was the biggest joke in the Western Hemishpere. I have seen more recent CVA revolver kits (1860 Army but with brass frame) and it is pretty good quality. (Pietta)
DGW has a good selection of kits and you can carefully select so as to get the kit which meets your needs. By that I mean that some are already blued, some are less finished. Some of the kit listings do not include the original manufacturer, some do.
