Well, I have a '67 Chevy van with a 283 small block. Essentially the same motor, although mine doesn't have much in the way of smog equipment (It does have an added on EGR valve). The 350 was a direct descendant of the 283, which in turn came from the 265 that first appeared in Corvette in the 50's.
These motors have a reputation for being indestructible. Plus they are so popular it's probably no problem finding parts and people to work on them.
They are also relatively easy to work on. Mine is a bit more of a challenge because of the tight confines of the '67 van doghouse - but a full size car engine bay should be much easier.
Mine wasn't running too well when I got it around 2008. After trying a lot of things, I finally adjusted the valves, and found they had not enough clearance. Once I adjusted that (again, pretty easy), it ran much much better.
There are also all sorts of mods you can do with a small block. The one I probably will eventually do is to replace the two bore carburetor with some sort of fuel injection. I'm sure yours has fuel injection already. On mine, a previous owner upgraded the points style distributor with an electronic unit,which has been problem free. The one thing I don't like about the motor is the placement of the distributor at the rear of the engine, which is a bit awkward on the van. Fortunately the electronic unit needs little to no maintenance.