Yes. I've replaced several. Personally I'd avoid the sprung designs so popular in the USA. They make for extra resistance when passing work across and always seem to leave a lot more of the blade exposed than the British-pattern bridge guard (not crown guard, BTW). The design of guard for your machine can be clearly seen in this picture (from D.B.Keighley's web site
I just feel more at home with a guard which can be set-up to cover the blade at all times when surfacing, despite a slightly tricker feeding action to master (which takes all of 10 minutes). Your machine appears to have the casting to hold the guard post, so you may well be part way there already. There's also the fact that if you are trade the American-style swing-away guard is not legal here, so your insurers won't like it, either. The best design I've ever used is the SUVAMatic guard
but they are really expensive but probably the safest design around. Next best option is probably the parallel arm bridge guard
supplied on many modern European machines:
Neither of these are cheap, but they are better designs than the traditional bridge guard and it may well be possible to engineer the parallel arm type yourself.
Incidentally your machine is a Whitehead, not a Cooksley. See here
for details (and a bit about the Wadkin BRT)