I have a 95SR, and the engine was supposedly replaced with a rebuilt engine a few months ago. Without going into too many details just yet, let's just say I am growing more and more suspicious that this was not the case.
Is there a serial number on the block somewhere? Am I correct in assuming that in a true, "long block" rebuild, the crankshaft pulley and timing covers would be replaced. (Among other things of course.)

When I was working at a dealer (though not a Mitsu dealer) and we rebuilt/replaced an engine, we reused the old timing cover(s), valve covers, brackets, pulleys, etc. unless it was necessary to replace them. What's up? Is it not running well? If the only problem is that they re-used the timing cover and the crank pulley then I wouldn't worry about it. If it's smoking or knocking or something like that, then I'd worry. Was it done at the dealer?

I wouldn't anticipate any pullies or covers to be replaced unless they were damaged - and then only if they would cause a problem.

All bearings, rings, seals and gaskits should have been done.

Doesn't help you much now,
but the heads have 2- digit numbers cast into them, in rather large digits. They're all different (enough, like a date code or something)
that you can tell which head is which, and if you had gotten the same 2 numbers, odds are very good that the engine's the same.
(mine has 9 and 32- that's how I kept left and right identified. Not that it really matters at all...)

I seem to remember that there's a number on the back of the block, on a flat, machined pad close to the ehad sealing surface- but I don't think that the number matches the VIN or anything as easy as that...
fwiw,
t