Hi Natasha,
Great question!
There are not more codons than those in the chart.
Non canonical amino acids can be made in two ways in the body:
1. Non ribosomal peptide synthetases (enzymes that perform synthesis of proteins like ribosomes, but don't scan an mRNA to get the order of amino acids).
2. Post-translational modification by other enzymes, oxidizing and reducing select canonical amino acids to transform them into the desired non-canonical amino acids.
I hope this helps!
Katt