We could count the scope of Interbus's network, at least 13 jumps from the HQ in Ourapheh.
It is noteworthy that with the highway gates to Yulai, the amount of systems in range might have been considerably higher than it is today. (Ourapheh is next to Yulai.)
They have agents in the following systems:
Akes (14 jumps from Ourapheh), Alachene (8 j), Altrinur (13 j), Anher (10 j), Aporulie (5 j), Arifsdald (11 j), Auner (13 j), Aunsou (10 j), Bahromab (13 j), Bille (8 j), BWO-UU (Jove, unreachable), Ethernity (4 j), Floseswin (11 j), FR-RCH (Jove, unreachable), Grispire (10 j), Haatomo (9 j), Heorah (6 j), Jakanerva (15 j), Jarizza (17 j), Lasleinur (12 j), L-TPN0 (Jove, unreachable)), Lower Debyl (14 j), Mabnen (15 j), Mastakomon (18 j), Maturat (14 j), Narai (15 j), Osvestmunnur (17 j), Otitoh (18 j), Remoriu (15 j), RF-GGF (Syndicate, 11 j), Tollus (16 j), Uchoshi (19 j), Uotila (13 j), Vaajaita (13 j) and W6H6-K (Jove, unreachable).
The agent furthermost from Ourapheh is in Uchoshi, if we ignore the agents in the Jove Directorate.