"Richard, you may get a number
"Richard, you may get a number of opinions, but I don't think anyone can really give you a difinitive answer as to how long a given motor will "live".
1200 hours may sound like alot when alot of outboards of the same vintage may have less than a couple of hundred.
But I would consider this - they have obviously been maintained or they would have gone bye-bye a long time ago. I put between 70-100 hours a year on my outboards and 2 of them are 87's, so while I can't give you an exact count, they probably have more hours on them than the (mere) 1200 hour engines you are looking at.
Unless you want to pull the head or perhaps the exhaust manifold and get a look at the cylinders for obvious signs of wear, your best bet is still a compression test. Almost all engines, even those 30 or 40 years old, often look great with the hood off - as long is nothing is rotted, ripped out or frayed - you can't tell much more without getting at it with a meter...
Consider the asking price - they may need a rebuild sooner rather than later - if that cost is factored in, and the rig is still a good deal, go with it - but hey, you could get 3000 hours out of them before that happens..."
