Maybe a dumb question (or two)

[BleeckerSt_Girl]

Yes, I have the Alex Ace-19 rims. I'd love to have either 25s or 28s.

Can anyone recommend a higher pressure tire?

Any tire that is thinner will be pumped up to higher pressure. Fat tires get pumped to lower pressure. It's a matter of physics, not tire brand.
Every tire will have it's maximum pressure recommendation printed right on it.
If you get a narrower tire like a 25 or 28, it will automatically be a 'higher pressure' tire than the ones you have now.