Excalibur provides a variety of terminators that includes, 78 ohm, 3K ohm and others.

ESI-T78
78 ohm terminator for inline couplers
ESI-T5078
78 OHM, 2W, 1%, PL75 TYPE CONNECTOR (TNG1-4-78)
ESI-T501K
1K OHM, 1W, 1%, PL75 TYPE CONNECTOR (TNG1-4-1000)
ESI-T502K
2K OHM, 1W, 1%, PL75 TYPE CONNECTOR (TNG1-4-2000)
ESI-T503K
3K OHM, 1W, 1%, PL75 TYPE CONNECTOR (TNG1-4-3000)
ESI-T7078
78 OHM, 2W, 1%, PL155 TYPE CONNECTOR (TNGM1-4-78)