ordinarily for 300 someone would recommend a 6" or 8" dobsonian reflector -good light gathering & can easily see saturn's rings, jupiter bands and its moons & close up views of the moon. when you look at the size
here , youll see it will not fit into your bags
the smallest telescopes for size are the CATS [cassegrain] either a schmidt or maksutov -they are a folded mirror design so are very compact
as you are travelling most likely you will buy much more scope in the US, what part of the states are you going to? the big US stores often offer free shipping & you dont have to pay GST f you buy from a store in a diff state to where you are [its cheaper to buy online then go inot the store & pay the VAT]
this
site lists some cassegrain scopes
you could also look for a refractor -they offer good quality images but have smaller lens/mirror for the same cost -you may still be able to get the astronomers without borders ED80 for a good deal
here NB you wil need a strong photo tripod to mount it, the 130mm dob
here is small enough to travel with, has its own mount & will show you the objects you requested
the ed80 would be my pick -it will retain the most value -and you can use it for photography later if you wish
stores in the US i like/use are optcorp. B&H, astronomics