But, even so, for most of us, the blocks we want (and acquire) are the old ones, found on eBay or Etsy or through one grapevine or another. Most of us don't have the tools, or the knowhow, to make our own, and the outfits that make 'em professionally these days want quite a bit of scratch.
I've been told (and I've seen corroborating evidence) that a reasonably competent woodworker can indeed knock out a good hat block. I know of a fellow who worked from numerous detailed photos of a particularly desirable block (a No. 52) to make what looks like a perfect copy.