Cookie-cutter guns are fine and I like to look at Doc44's beautiful guns as much as anyone, but as the poster said, the current crop hardly qualifies as some sort of religious artifact. I think there is also a lot of interest in an S&W (to me, at least) that has been carefully modified to suit a purpose and received corresponding use by its owner. I'll be pleased to see your revolver when it is done and hear your shooting results. So don't forget to post the pics and info.

The barrel is probably not going to look like a 66 barrel because the 686 barrel does not have a lot of taper, so it will be somewhere between what it is now and a big 66-looking barrel - but it should be just fine.

As to cost, good work is never cheap. If you are going to do a project like this, it should be done carefully, by someone with an eye for such things. People spend $250 on worthless junk like cokes or french fries in a year. It's just money. At least your modified gun won't be clogging your arteries.