$100 budget limit on power cable wouldn’t get you much. Wait until you are in a $400-$500 range. Making baby steps in this hobby is usually a waste of time and money.
But…if you want to spend $100 now to upgrade the power cable just get the best plugs you can get for $100, chop you stock cord plugs off and attach the new ones. If you want to make the power cord prettier, get an expandable jacket but I wouldn’t bother. Something like the
Viborg rhodium plated plugs should make a nice improvement when used on a 14awg stock power cable.
You can just get a better quality cable later on and transfer these plugs there.