There are no known pictures of Richard in this film. He was simply in it, and also was in the "Carry On" special in the UK.
Says Richard of his time filming as a stuntman...
"My one lasting memory of Carry On Cowboy was the riding audition. The production team had gathered together around twenty or thirty ponies that they imagined looked like wild mustangs, pintos, painted ponies, call them what you will, the only thing that they had in common was that none of them was really broken in.
The test was to ride one of them bare back with no bridle, only a rope halter without a bit, up to point A. Here- you were given a bow and arrow, which you rode with to point B.- fired at a target from the moving horse and then rode on to the finish. Simple?
I rode from the start to point A so well that I received a round of applause from my fellow riders - I took my bow and arrow and rode to point B - as I released my right hand from the rope halter the horse knew I was relying on his goodwill and decided not to give it. With a short, smart little kick I went shooting between his ears and 'bit the dust', as they say!
'Oh, Dear!' cried the first assistant.
'Can I try again?' I asked.
'Yes' - they all chorused - 'Let him try again!'.
I repeated the test, this time on a different horse. Same routine, up to point A - fine - take the bow and arrow- fine. Ride to point B - release the hold on the halter - and boom -straight between the ears again.
A man called 'The Horse Master' smiled the most supercilious smile I had ever seen in my life at me- God! how I hate insult to injury - And he swanned his way over to the animal that had just thrown me and as if to show everyone what a complete and totally useless little shit I was, mounted the beast with style and grace.
Boom! He went sailing over the horse, a tickled crowd and a 'serves you right' me. I only did about 3 days' employment on the film, but I did get to watch a lot of filming as I wanted to know everything about the movies I could, and I must say that I was never asked to leave the set, even on days when I had no right to be there what-so-ever, and there were a lot of them!
I found it thrilling. Still do!"
EDIT 7/20/2012: Arthur believes he may have spotted Richard in the film. He has been on a bit of a mission to locate Richard in both Carry On and Casino Royale. I can't tell conclusively, but it could well be. Hopefully screen caps to follow.