Stuffing Box ID and Adjustment

A few drips per minute is not bad, you might be able to grease that seal as advised and finish out the summer.   Your full repair is a good off season job so you can take your time.
The ARE Shaft is the best fix for sure and I bought one for my boat.
With that said I have replaced 3 of the single taper shafts and they do come out without that much trouble if you are careful and logical.   On my 78 Nautique I had to replace 2 shafts. On our 95 I replaced one. I unbolted from the tranny, Slipped a socket just smaller than shaft size in between the tranny and the coupler and used the 4 bolts to slowly and evenly tighten and push the shaft out.   I may have needed longer bolts for this but it was a few years back and I don't remember. But it worked well and did not take long, 30 minutes maybe. This worked twice.   On my 95 the boat ran so long with a bent shaft, previous owner, that the coupler slid off when I loosened the set screws..
It was worn out.   Putting the coupler back on takes some thought but there is good advice on here to properly heat and install those and it was done for years prior to ARE but the ARE is really nice and easy to work with.

But your shaft may be fine, check first, if a new one is needed ARE is a great option.

It's not a safety collar !     It is the front half of your 80's Supra PSS.
note the o-ring inside. (pic below)
When your boat was new it had a rubber bellows instead of the straight hose it has now.
Someone did some freelance hacking for you before you got there.
I would take Pete's advice and replace the whole schmere with the traditional packing seal.
And I think you already got the memo on the PVC.



Here's what it kinda looked like in '86 - except in the late 80's Supra did not have the water feed.

Didn't get to this over the winter, had some other things come up.

I ended up having to cut the shaft. The safety collar had to be cut off. I nicked the shaft in the process.

I'll be ordering a new double taper shaft and shaft seal this week from skidim.

I'm leaning toward a dripless shaft seal. I don't have a stuffing box. Buying a traditional set up isn't much cheaper than the dripless.

Can I test the Cutlass bearing? Don't want to replace it if I don't need too.
Any other "while I'm in there" things to consider?

Parts ordered including cutlass bearing.