I bought a dual voltage hairdryer in the US way back in the 80s, and a cheap one at that, so it's definitely something to check on one you may already own.
Measuring cups and spoons are pretty much available everywhere now. I've even seen them in a pound shop, albeit not very nice ones. All the major grocery chains sell them, but expensive for what they are. I would check Home Bargains, Wilko (Wilkinson), Dunelm Mill or B&M Bargains (or any similar store) and I'm sure you will find measuring cups/spoons quite cheap. No need to wait for the next US trip.