Chris,
No idea with the photo, but think it is after they left Ricardos at Shoreham. Where did the photo come from?
I remember someone from R Yeo telling me, before they were withdrawn from their unit, that they were re-equiping with L/R recce vehicles and that the Foxes were going to Mexico, with a differnt turret. Some I saw much later in a dealers yard, post-Ricardo, had feint chalk wording, "Mexico"on them ,so story ties up. So it looks like R Yeo vehicles were used for this project, as to how many, don't know. I believe your Fox is from A Sqn (Royal Wilts Yeo) R Yeo, so again this ties in.