[Sol]

Brian, MSE only make parts for signals. Ratio make kits.
To the best of my knowledge, there are no RTR semaphore signals for UK modelling.

 

[Sol]

At 15-20 GBP. I would get a few.
By the time one buys a Ratio Kit + a Tortoise together with the time building & installing, having a RTR that may just be 5-8pounds dearer would be good value.

 

[Sol]

I maybe proved wrong but I believe the majority of model railway/railroad modellers are not so nit-picky, that they would not use any item that did not exist in the flesh on their representation of such a line.
My Empire is loosely based on GWR/WR but I have no qualms about running locos that may or could or should have run on those rails & so to get another item which will make it look more like a rail network like RTR semaphore signals would be a blessing.

For those who follow the actual railway/railroad & must have the correct type of post, etc, good, but we must not forget that the hobby has a few compromises & to the majority of users; having the correct type of signal post would be a minor part of their enjoyment.