Djokovic and Murray's sticks don't have codes. They are completely custom racquets with custom molds, layups, and drill patterns. To date, these are the only two Head players who don't use coded racquets. The codes are as follows, keeping in mind that the .1's are 18x20, the .2's stiffer 16x19s, and the .3's flexier 16x19s:
--TGK219.1,2,3--Pro Stock Extremes
--TGK231.1,2,3--Pro Stock Radicals
--TGK237.1,2,3--Pro Stock Prestige Mids
--TGK238.1,2,3--Pro Stock Prestige MPs
--TGK262.1,2,3--Pro Stock Thin-Beamed Speed Pros
--TGK263.1,2,3--Pro Stock Thicker-Beamed Speed Pros
--PT57A--Pro Tour 630
--PT57E--There's a lot of controversy. Some believe it's a stiffer layup of the 630, whereas others believe it's the i.Prestige mold and layup. Head touring pros seem to think it's the old 630 though, as Ernests Gulbis told me after a match that he uses "the old blue one."
--PT10--Prestige Classic 600
Hope this helps.