Don't forget these:
US&S type B Block/Distant Semaphore, <kuid2:46075:25711:2>, made by AltoDave, for Trainz 2004 and up
US&S bype B Home/ Distant Semaphore, <kuid:46075:25710>, made by AltoDave, for Trainz 2004 and up
Signal US&S type B Home/Distant Semaphore TS2010, <kuid2:69871:2065:1>, made by philskene, for Trainz Classics 1 & 2 and up
Signal US&S type B Block/Distant Semaphore TS2010, <kuid2:69871:2064:1>, made by philskene, for Trainz Classics 1 & 2 and up
B&M US&S Style-B Home/Home Semaphore rusty, <kuid:60002:100031>, made by ScottyW, for Trainz 2009 and up
B&M US&S Style-B Home/Home Semaphore, <kuid:60002:100033>, made by ScottyW, for Trainz 2009 and up
B&M US&S Style-B Home/Distant Semaphore, <kuid:60002:100032>, made by ScottyW, for Trainz 2009 and up
B&M US&S Style-B Block/Distant Semaphore, <kuid:60002:100030>, made by ScottyW, for Trainz 2009 and up
GRS 6 RH light relay box semaphore signal with Red boards, <kuid2:61556:2410155:1>, made by seniorchief, for Trainz 2009 and up
GRS 9 light relay box semaphore signal with Red boards, <kuid2:61556:2410149:1>, made by seniorchief, for Trainz 2009 and up
GRS 9 RH light relay box semaphore signal with Red boards, <kuid2:61556:2410152:1>, made by seniorchief, for Trainz 2009 and up
3 light Semaphore Bridge Signal, <kuid2:61556:2410143:1>, made by seniorchief, for Trainz 2009 and up
GRS 3 light Semaphore Signal, <kuid2:61556:2410138:4>, made by seniorchief, for Trainz 2009 and up
GRS 6 light LH semaphore bridge signal with Red boards, <kuid2:61556:2410150:1>, made by seniorchief, for Trainz 2009 and up
GRS 9 light LH semaphore bridge signal with Red boards, <kuid2:61556:2410151:1>, made by seniorchief, for Trainz 2009 and up
GRS 6 light Semaphore Bridge Signal SQ, <kuid2:61556:2410146:1>, made by seniorchief, for Trainz 2009 and up
GRS 9 light semaphore signal bridge with Red boards, <kuid2:61556:2410147:1>, made by seniorchief, for Trainz 2009 and up
3 light Red Board Semaphore Signal LH, <kuid2:61556:2410145:1>, made by seniorchief, for Trainz 2009 and up
3 light Semaphore Yellow Board Signal LH, <kuid2:61556:2410144:1>, made by seniorchief, for Trainz 2009 and up
3 light Red Board Semaphore Signal, <kuid2:61556:2410142:1>, made by seniorchief, for Trainz 2009 and up
3 light Semaphore Signal, <kuid2:61556:2410141:2>, made by seniorchief, for Trainz 2009 and up
GRS 3 light Semaphore Signal, <kuid:447944:1049>, made by Kris94, for Trainz 2009 and up
I found these typing in 'semaphore', selected 'Trackside Accessories' in the category, and selected 'Title'. You'll get a lot more if you select 'Description'.