source for 5-methyl-dCTP?

[YHSUN at imb.as.tw]

Stratagene has a cDNA synthesis kit which uses 5-methyl-dCTP for its 1st
strand cDNA synthesis. This protects certain internal restriction sites
from being cut during digestion of the added linker. Sounds reasonable. But
does anyone know a commercial source for 5-Me-dCTP? Thanks in advance.

Henry Sun
Institute of Molecular Biology
Academia Sinica
Taipei, Taiwan