Yes they can. The stocks that came on the SAUM Ti rifles had magnum barrel channels, but they are obviously all short actions. You should be fine opening up one of the LA stocks to fit a Mag barrel.
If you don't already have a stock to do that with, I have a LA Alaskan Ti stock that already has the magnum barrel channel that I'm not going to use. You can send me a PM if interested. It is a BDL stock, and as far as I know, that's the only way they are available from B&C. I've not had any luck ordering a Ti stock from anyone in ADL config with the mag barrel channel.
Kevin