Green Mountain no longer makes a "drop in" replacement barrel for the T/C's and Lyman's which is why no one has one.
That leaves you kinda/sorta three options.
1) check the "for sale" sections and hope to find what you are looking for used/nearly new - this would be your most economical option (unless the barrel turns out to be less that pristine)
2) buy a drop in from The Gun Works - you specify a number of the specs but they build a "drop in", pretty close to the product you used to get from Green Mountain.
But wait, the price tag is $350 (plus shipping and maybe tax depending where you are).
I believe Stonewall Creek has said they will provide the same service but have not (to my knowledge) published a price as of yet.
3) Get one of the shops to put together a barrel for you.
You would choose the barrel (150-265 bucks), the plug (35), the rib (25), thimbals (say 20), sights (15-75 unless you want something really specialized) and then pay the "gunsmithing" to put it all together -
Cut and crown the barrel (or leave it at 36") - 20 bucks
Install the plug - 25
Cut dove tails for sights (2) - 40
Install the rib - 60 minimally, maybe 90 bucks
The cheapest I come up with here is $390 but you could drop 500 bucks without blinking fast.
Either option 2 or 3 would also leave the barrel "in the white" so you would either have to blue it or have it blued unless you wanted to leave it in the white, which is acceptable from a function point of view...
