Thanks. the learning curve has been high for me.
Well, if you think about how the pump is built you will see that what is going on here is pretty straightforward and something you could easily fix yourself.
As you can see in your picture, the front part of the pump is where the water is; that's the part of the pump that has the hoses attached to it. The very back part of the pump is where it is bolted up against your engine. The engine is what contains the oil, of course. In the middle of the pump is a chamber that has a weep hole. That's where the oil is leaking out.
The pump has two seals. One keeps the water from leaking through the front part of the pump and out the weep hole, whereas the back seal is what keeps the oil inside the engine and not weeping oil through the weep hole. Think of that weep hole as a sort of alarm. Nothing should be coming out of the weep hole, regardless of what is going on inside of your engine. If water is coming out, it's the forward seal that's bad. If oil is coming out, it's the back seal that has failed. If both oil and water are coming out, then both have failed--though the probability of both seals going bad at exactly the same time is low.
The fix is simple: either replace the seals in the pump, or just replace the entire pump. If you don't want to replace the seals yourself, ship the pump off to Depco Pump in Florida and let them do it. They are excellent, and having them refurbish the pump in most cases will be cheaper than buying new. (I say "in most cases" because sometimes there are other things that get worn out in these pumps that can make them so far gone that rebuilding them is not economically viable. But if you send it to Depco they will be able to tell you the best course of action re: repair or replace.)
As for swapping out the pump: You don't need a mechanic to do that. Just remove the hoses from the pump (with the seacock closed!) and the bolts (two of them or whatever it is) that are holding the pump to the engine. The pump will just pull off. The shaft is keyed, so when you reinstall it just line up the flat part of the shaft to the orientation of the key inside the engine, bolt it down, hook up the hoses, and you should be good to go.
As a broader consideration, it will be best to get up to speed on being able to do basic maintenance on the engine yourself. I'm no mechanic either, but I've learned to handle all the main maintenance items myself. If you pay a mechanic to do everything the cost to maintain your boat will soon become prohibitive. Additionally, there are lots of really incompetent folks out there who simply hang up a mechanic shingle and charge you confiscatory rates to screw up your engine. This makes no sense when you can screw up your own engine for free. But seriously, swapping out this pump is one of the simpler tasks you can do on that engine. With a bit of coaching from the forum you can definitely do this.
I'm not saying that there is no place for a good mechanic, by the way. But you don't need one for this.