Not being completely satisfied with my answer I decided to do a little more local research.

Try Value Pet Clinics
They have a number of local offices, I called the Renton clinic.

Costs would be:
$4 set up a file
$28 examination fee
~$15 for medications
$37 to send stool sample for testing for other parasites

So total cost would be around $85.
They take walk-ins for non-surgical visits with no appointment necessary.

http://www.valuepetclinic.com/

(425) 255-5678

3901 NE 4th Street, Suite 103
Renton WA

Thanks, that's definitely a better option. What frustrates me is that our old clinic, which has treated our cat since she was a kitten, insists on a visit plus lab tests for everything.

When I was a kid, if I or any of my siblings had symptoms of strep throat, my mom could call the doctor and he would call in a prescription. For a human person.

We've got video of the damn worm - I know it is a roundworm, unless she has some sort of never-before-seen alien cat worm - and the vet insists that she come in, have a full exam and send out a sample. We just need to find a new vet.

Ah, the days before everything was litigated beyond reason.

I think they will want to do the stool sample lab work, but you may avoid that by signing something (I didn't get that clarified, sorry). Your cat may have other parasites that are not so easily seen so it may not be such a bad idea. But be sure to take in the stool sample (and your video, too).

http://www.petco.com/petco_Page_PC_productlist_Nav_1284_N_23+4294956681.aspx

No prescription cat wormers from Petco.

Russ, your answer was right on and made me re-think my course of action here. I take the cat's health pretty seriously, but her vet has been working my last nerve for years now, and I've figured out today that she is way more expensive than some vets closer to us, so it's time to find a new one. We called one place and they said to wait until we see another worm and bring a sample in then - they were not overly concerned since we'd only seen the one worm (not plural worms) today. So, kitty gets her doctor visit and gets rid of her wormy passengers, and you sir, you get the shroom.

Glad you decided on finding a new vet and a visit.

Does no good to worm an animal and not prevent future parasite infection. For example, tapeworm larvae are vectored through fleas, so it's important to worm and use appropriate flea treatment.

A vet considers proper medication, doses and duration, depending on the worm, while keeping an eye on their effects on organ functions.