jjeff1:I'm sure technology has changed, I know masks fit much easier, but what else has changed and what's best to spend my money on?
Most of the changes have been cosmetic. Masks are no better or easier to fit than they were 30 years ago. If it's not beyond repair, don't replace it. I have some new gear that's about as old as your old gear.
jjeff1:Tank: 1970 VOIT steel tank.
Have it hydroed, tell them when you drop it off you'll want to see the report on the results. That should make them actually do the test. If it's been treated well, it should pass.
jjeff1:BC: 1990ish US Divers Aqualung Pro Line BC
- appears to work, but is losing air just sitting here, so has some type of slow leak. Seals I'd guess, but this is probably my #1 item to replace.
Find the leak. If it's in the inflator or over pressure valve, you should be able to fix it. If it has a hole, you may have to replace the bladder.
jjeff1:Regulator: 1990ish Conshelf 21 1st and 2nd stage
Octo: 1970s Calypso
Pressure Gauge: 1990s US divers
Get it serviced, it'll be fine.
jjeff1:Depth Gauge: none
Get one. There was no excuse to be diving without either a depth gauge or a computer 20 years ago. I was (still am) using both.
jjeff1:Fins: 1990ish TUSA Mini Liberator - Plastic fins, only 20 inches long, but a good size for a skinny me.
They were never good fins. You can use them, but Scubapro Jets (a much older design than your Liberators) will serve you much better and you can pick them up for very little off e-bay.
jjeff1:Mask: new! But doesn't fit really well, I'll probably replace it.
A well fitting mask is important, replace it.
jjeff1:wetsuit: none
You'll need one, especially in NY.
jjeff1:I'm looking to re-do my open water cert with PADI along with her.
Having a YMCA certification, you will probably be disappointed with this choice unless the instructor is really outstanding.