Track of the Wolf's bbl liners are made by T.J. (Gateway?) Enterprises in KY.

I think they are a bit cheaper ($/inch) than Track's prices when you buy direct.
The last contact info I have for them:

TJ's Enterprises
3652 Neltner Rd,, Alexandria, KY 41001
859_-635-5560

They can probably help out determining if the bbl can even take a liner of that caliber,,breech and muzzle dimensions, ect.
Plus they may be able to help w/a bore/groove or twist not listed on TOTW site.

Good luck in your project,,certainly one worth putting the time and effort in.
(How about a re-bore/re-rifle to .500 x3" BPE)