1967-1974 on the SR: 4BIG 7049-58, 4CIG 7337-7438, 4VEP 7701-7894, 2PEP 2001, 4PEP 4001/02; ScR Class AM11 (TOPS 311) 092-110. While not in the same volume as years prior to 1967, I wouldn't say that it was 'very few'.
Just the image that I would like to portray on any layout I get the space to build - It hasn't stopped me trying to accumulate the stock for it, though. The blue stock behind looks like a reasonably new 4TC unit, the Mk1 Blue/Grey BSK has the early small lettering, mounted higher on the blue part of the bodyside than was to become standard.
1966-74 was the time scale that my friends and I were scurrying around the London area trying to 'cop' as many of the dying breed as possible and is the period of British railways (note the small 'r') that I remember the best. And would like to portray in model form.