Getting back to Colin's original questions, while I don't have any specific information on Canada's interest in the Saladin, I do know that the Fox and Scorpion (the British Army's designated replacements for the Ferret and Saladin) were trialed by the CF between August 1970 and April 1971.
According to an article in the 1970 edition of 'The Strathconian', in August of that year Captain Bob Caldwell headed a team that traveled to Bovington to trial both vehicles at the RAC Centre for four months. Just before Christmas two of the Foxes and two Scorpions were brought to Canada to undergo winter trials at Wainwright (January to March, 1971).
In Canadian use the Fox was to be a possible replacement for the Ferret (it was after all just a Ferret IV with an up-gunned turret) while the Scorpion was to be introduced as the DFSV (Direct Fire Support Vehicle), a new requirement for the Canadian-based armoured regiments of 1970.
The article in 'The Strathconian' indicates that the winter trials went well and the personnel involved were generally happy with the results, but the trials were to continue on in the UK. Whether these two vehicles fit the bill or not, we know now that neither were adopted. The Ferret continued on until after the 1976 Olympics in Montreal, and no DFSV was ever acquired.
As to the Vixen, well, it was a non-starter. Not even the British Army bought it.
I believe the reason the Canadian Army did not purchase the Saladin when it purchased the Ferret is due to, as you guessed, doctrine. The British Army employed the Ferret / Saladin combination in its Armoured Car Regiments, which are a Corps-level asset. During the post-war years the Canadian Army was concentrating on a Division structure. This required armoured car reconnaissance only in the armoured regiment, where the tank could provide any heavy support required. When the Army did organize an armoured car regiment in 1964, it was an all Ferret organization.
Hope this helps.
Cheers,
Dan.
