Excalibur has a wide variety of 1553 transformers.

ESI-T15-1
Ratio - 1:1 / 1:.707 Package: PC Mount A M2103827: -1
ESI-T15-1-1
Ratio - 1:1 / 1:.707 Package: PC Mount 2
ESI-T15-2
Ratio - 1.4 : 1 / 2 : 1 Package: PC Mount A M2103827: -2
ESI-T15-3
Ratio - 1.25:1 / 1.66:1 Package: PC Mount A M2103827: -3
ESI-T15-6
Ratio - 1:1 / 1:.707 Package: Flat Pack F M2103827: -11
ESI-T15-7
Ratio - 1.4 : 1 / 2 : 1 Package: Flat Pack F M2103827: -12
ESI-T15-10
Ratio - 1:2.12 / 1:1.5 Package: Flat Pack F M2103827: -15
ESI-T15-20-1
Terminals 1-2:3-4 Turns Ratio - 1 : 1.41 Package: PC Mount C
ESI-T15-20
Terminals 1-2:4-3 Turns Ratio - 1 : 1.41 Package: PC Mount C M2103827: -5
ESI-T15-40
Ratio - 1:2.5 / 1:1.75 Package: Flat Pack F
ESI-T15-45
Ratio - 1:2.5 / 1:1.79 Package: Flat Pack F M2103827: -27
ESI-T15-85
Ratio - 1:2.5 / 1:1.79 Package: PC Mount A M2103827: -25
ESI-T2725EX
Ratio - 1:2.5 / 1:1.79 Package: PC Mount 2 M2103827: -25