Right here. https://www.aomci.org On the left side if the screen, Click on "Upcoming Events". I suppose there is a link to your local chapter also, but I didn’t check that out.

Well, looks real nice so far. Looks like the electric start was set up to be controlled at the engine, so no external wiring harness to worry about. I am "assuming" you intend to use the engine as a tiller control, not with remote steering/controls.
OK, gas tank and stand not included, no big deal. But, you say the owner changed the gear lube, so you won’t be able to tell much by cracking the lower drain screw because the gear oil is new. Unfortunately, you can’t really judge the gear case sealing status without pressure testing the gearcase, or just running the engine a few times then changing the lube again to check for water. You can’t judge the condition of the clutch dog/gear lugs by running the engine in a barrel, that can only be judged on a boat in gear under load.
You can check compression before buying though, that engine probably will show at least 110PSI. The pictures don’t show any evidence of overheating, the paint appears to be good/unburnt/not blistered on the cylinder head/exhaust cover.
So, the gamble here is gearcase condition. But, I’m thinking that engine didn’t survive so nicely all these years being poorly serviced or with a leaky gearcase. I would probably be willing to gamble on the gearcase being in good condition, but I’m sure the seller would not be willing to take the engine back if problems were found. So, use this unkown as a bargaining chip unless the owner is willing to refund if gearcase problems are found.
Again, plan on doing some servicing next winter in order to ensure longevity. There is no need to "reseal" the gearcase unless water leakage is noted. But, you do want to pull the gearcase down, and change the impeller though, unless the seller can prove this was recently done.
Please take the time to look the engine over carefully. Look for bent/cracked castings, or signs of being repainted. Look closely at the gearcase skeg, be sure it isn’t bent/cracked/worn down. Spin the propeller, look for signs of a bent prop shaft. The model and serial number on the powerhead ID plug should match the numbers on the stern brackets also.
Listen to the engine while it is running, make sure it pumps water and idles OK. It is normal for these engines to fuss and spit while warming up, but it should settle down and idle nicely after a few minutes of warm up.
So, I guess what I’m saying is that this engine looks like an nice candidate for purchase. But, I am not there and can’t see the engine up close. It surely "appears" to be an original low hours survivor in good condition. I’m not sure how much faster it will be than the standard 18hps of the day, but there will be a noticeable difference. Electric start is surely a nice option to have also. Try to negotiate a little lower price, but know the engine is worth the asking price is it truly is everything it is advertised and appears to be.
PS- I am assuming you are looking for a short shaft/standard length" for a 15" transom, converting it to a 20"/long shaft model would probably cost you a few hundred dollars.
Good luck, hope it works out for you. Don