If that is a 5.5 HP, then it is a 1958 Oliver-made Wizard...probably one of the more rare varieties. In good condition, it is valued at $125 according to the Old Outboard's Book by Peter Hunn. See last post on value versus actual selling price.
The model number should be a WH6A then, making it a Mercury-made wizard based on the Mark 6A. The value is probably not much more than $50 based on Peter Hunn's guide, but if it runs and is in decent condition, you may be able to get more for it if selling. Again, the value estimates may not equal what you can sell it for. Take a look on ebay for Mark 6/6As or Wizard Super 5s and see what the bidding prices are.
They are really not that rare of a model despite age, so they tend not to go for lots. The fact that it is a Wizard does add to its "collectibility." I bought mine for $100, and it ended up being more work and costing more money then I was up for...but that is just me.
I am looking for information as to what would be a fair buying price. I looked on eBay and nothing turned up on the wording you recommended for a search or variations.
I am going to look at the motor Monday. Any suggestion on what to look for regards weakness.
As far as known issues, I believe the biggest complaint on the Mercury's/Wizards of this vintage are weak drive shafts and seals, which can be replaced if you have a problem. Many have leaking lower unit seals which allow water in and can ruin the gears over time if not fixed. If you drain the gear lube, and it is milky colored, you have a problem. Some folks may use grease (Lubriplate #105) as a work-around. I would argue that they are one of the more difficult models to work on, as the lower shroud does come off easily, making it a little complicated to get at things. The impeller change is more challenging than an OMC, particularly lining the driveshaft back up with the crank when putting it back together. But, it isn't impossible to work on and you really don't need special tools like some Mercs.
They have Phelon magneto ignitions. If you don't have spark on the cylinders, the coils are likely shot and are about $40 each to replace. I would also check the compression. I wouldn't touch it much below 85PSI, and make sure the two cylinders are within about 5PSI of each other. Also, don't buy it if it has been in saltwater.
That said, the comet powerhead is known to be very reliable, and if you find a nice one, it would make a great little fishing motor. They are a neutral clutch (no reverse gear), but they can be fully rotated to go in reverse. Lots of parts available.
JP thanks for your reply. I and a friend when over and tested the motor it was just as advertiser. It is in excellent condition, started right up. Nothing was missing, prop was not chip or anything, all of the marking were bright. It ran very smooth. I pick up the motor, stand, 5gal gas tank with all of the proper hook ups. Thanks for all of your input.
For peace of mind check the impeller. If it is not
new looking spend the money to replace with new.
The time to check an impeller is before the motor
overheats and seizes up not after. Preventitive maintenance costs less than deferred maintenance.