The male part of the Dr. Martens buckle broke on my favorite sandals.  I was not able to find anything sized correctly via retail, so I created my own.

It does not have the curvature like the original (see picture) and it fits very snuggly.  I slip on my sandals, not actually using the buckle, so it works for me.

Since I just needed it to hold the strap in place and it be ‘buckled’, I printed it in PLA.