RE belt shrinkage:
the "cure" is to begin a serious program of short walks, followed by short hikes, then adding a backpack, increasing the backpack weight, then progressing to, for instance, overnight hikes to a Lake Tahoe bugout location etc., Somewhere during this time, the belt will give up and relax to it's original length and your problem will be solved.
Of course, you could also go to the local Tandy leather store (I think they are still in Reno) and buy an oval leather punch. I think these are available online also, but I haven't searched. They are a good tool to have in the prepper tool chest.