Ammo is easy enough to find and from what I've seen starts at $25-$26/20rds for PRVI 405gr SP and goes up from there. Just keep in mind not all factory ammo is safe for use in TD's.
I have a rifle and a carbine. The rifle is pleasant to shoot(to me anyway) but the carbine is rather stout. I shoot either Remington 405gr factory ammo or hand loads the duplicate it. Mostly hand loads anymore, the factory stuff is about $40 a box now.
I haven't kept up with prices lately but first of the year I considered getting another TD but happened across a deal on a LE No.4 Mk.1* T I couldn't turn down instead. Average going price on Gunbroker for a TD rifle at that time was between $650-$850, depending on condition. Carbines were considerably more, around $1600-$1800 IIRC. Things may've changed by now, I don't know. The urge for another one has pretty much gone away now.