Timer Circuit 555 74123

I'm looking for some advice on a design project I'm working on.
Basically I need a circuit with an adjustable delayed pulse of approx
5-50ms as well as an adjustable pulse width of 8-11sec. I'll actually
have to build three of these, the idea is I need to activate three
individual devices at different times and have them deactivate in
reverse order approx 10 seconds later with one control source.

I'm think I can accomplish this with a couple of 555 timers. I'm just
probing around to see if someone has a better idea. I've had some
succes with a similar circuit using 74LS123's but this situation is
different in that I need the 10 sec pulse width. Any input is
appreciated. Thanks in advance.

.

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