I had a TCR 83 years ago in 243 Win. I regretted selling it and bought a TCR 87 in 32-40 which I am keeping. I had a custom shop barrel in 30-30 made before the fire at TC and got a good deal on a 223 barrel a while back. What I would really like is a 22 Hornet barrel, but TCR barrels go for way more than I will spend on ebay, etc.
By the way, the TCR was never made in a rimfire version. However, since it has a removable recoil plate in the receiver face, it would be possible to make an offset firing pin for it and have a custom barrel made. It would not be cheap and would not offer much over the Contender carbine in a rimfire IMO.