GG,

The bench stop I use: a 1/4" x 2" x 12" hardwood batten
that has two fixed bench dogs. The spacing of the dogs is
the same as the spacing of the dog hole rows on the bench.
Plop it in when needed, stow it when you don't. The bird's
mouth block used for edge planing small thin pieces also 
has 2 dogs. Simple, stable and you can have it the lenght
you want. An "L" shaped stop can also be usefull for small 
pieces that keep running away from your plane, two edges
help keep it in place.

regular stop, view from above:
_____
|        |
|  O   |   dog
|        |
|        |
|  O   |  dog
|____ |

"L" stop:
____________________
|                       O        |
|         ______________|
|        |
|   O  |
| ____|

Hope this helps,

Louis Michaud
Rimouski, Quebec