On the old engine the tensioner failure took out the crank? That's a little unusual - how did the crank go - snapped? (if so which journal did it let go at), bearing failure? I recognise that post is a year old, but I'm curious. Part of the reason I'm curious, is that the known causes of timing chain failure (essentially a lack of proper lubrication - see below - the tensioner is hydraulic and is heavily dependent on the availability of clean oil at the right pressure) can also cause crank failure (if taken to extremes) - I can't help but wonder if the one caused the other, or, neither was the cause, both are effects resulting from the same cause.
There IS a "silver bullet" for the timing chain tensioner issues - would you believe - regular oil changes at 3000 mile intervals, and the use of the correct grade of oil (probably 5w30/10w30 for your climate) and a good filter (my preference is the OEM Suzuki filter).
As far as parts go - I also have a preference for Suzuki Genuine Parts - but you should be able to pick up decent quality replacements from Parts Dinosaur.
Last thing - I know folks who have 200+, close to 300k miles on these things, with very few problems - and from what they tell me, proper maintenance is the key.