I don’t know if they make a true portable system, but they do make ductless mini-split systems, which are room or zone systems that are very economical to operate:
https://www.carrier.com/residential/en/us/ductless/
Yes, we put a mini split system in our master bedroom, so that we could leave the rest of the house at 75 and cool the master BR to 72.
I bet those Carrier mini split units are not made in the US, however.
I will have a look at those. Thank you so much.