[ hmm, a Pegasus Female, i would prefer to know the specific appearances, white coat black mane Red eyes. If that's not possible to find then that's alright.
Skillet the cook and Willow the farmer seems to fit the rough description. But i prefer a name change to "Kat" , i've seen "Grapple" being inserted in a rather creative way, i wonder if that's also possible. Well, we'll have to see what Telgin have to say then. Just to say now, i look forward in joining the guards, seems like you could use an extra markspony. see you in the game real soon everypony. (hopefully) ]
Ok, took a look at the two you suggested and here's their descriptions:
Willow: Wavy scarlet hair, slate gray coat, copper eyes. (She is currently in love with Longshot, so you know)
Skillet: Unkempt dark scarlet hair, slate gray coat, ochre eyes.
Willow actually has some combat skills already (dunno why, they aren't rusty so I don't think she migrated with them), and is quick to heal. Skillet is my best / only cook (grand master), and she sucks (clumsy, flimsy and quick to tire), so I think you're better off taking Willow if you want to join the guard. Or I can keep looking for more pegasus mares.
By the way, the description is up to you really. I've adjusted it for a few ponies here and there to keep things interesting since DF doesn't do a good job of that.