The delete pullies aren't that hard to find these days. Just put out a WTB on either MX6.com or ProbeTalk. I've had 2 of them come through here. (I can't fit the delete pulley on my car because... ermmm.... things.)
That thing looks very clean. Buy it.
The trans isn't the strongest thing in the world, but treat it well, and it'll treat you well. Strangely, they seem to last BETTER with a big turbo vs. the small IHI crap that it came with.
As for power ratings, underrated. The 145hp/190tq that it makes on paper happens to be exactly what i've seen all stock ones make on the dyno to the wheels. Even after 200k+ miles.
The motor will not die unless you've tuned it badly or ran it low on fluid. Virtually indestructable. Mine has 187k miles on it (original motor), i push it hard, and i'm pretty far from stock. (Read: horrifyingly fast on 20psi+)
The suspension, don't sweat it. Don't bother trying to get the factory replacements, they're expensive. Decent shocks, but expensive. Throw GR2s or Tokico HPs in there at a minimum. If you want adjustables, the 2nd gen MX6/Probe parts bolt on up front, require minor modification in the rear. I'm currently running all second gen springs/struts on my car, with 1g strut mounts. Works fine, and is CHEAP. ($340 shipped - $200 i sold the servo motors for = $140 out of pocket = challenge friendly.)
These cars are ridiculously reliable, the build quality is incredible, and they're an absolute joy to drive. In my opinion, they're one of the best cars Mazda ever made.
I'm quite literally the 14th owner of mine, it's been abused all it's life, and it might be the worst example of a GD-chassis Mazda i've ever seen in my life. It still runs obnoxiously well, drives great, and has a great way to break up my boring morning commute. (Loud pedal = better than coffee.)
Parts are cheap, they're easy to work on.
Oh, and gas mileage is good, too. Expect high 20s combined, over 30mpg on the highway.
Oh, a side note. Find out if it's 4ws or not. The 4ws is cool, but i wouldn't personally buy one. Parts are hard to find, and the rear suspension IS different. Mine is just my DD, and i prefer the simplicity of the 2ws to the cool factor of the 4ws. YMMV. I'm not telling you pass it up if it's 4ws.