Reddit mentions of Procomm 3 feet Coaxial Cable Jumper with PL259 Connectors

Sure thing. This sub doesn't seem to be overly active so if you have any more questions or run into trouble, you might want to ask them over in /r/amateurradio. It's really the only place on the internet where hams hang out that don't seem to mind answering CB radio questions.

I'm not sure what your budget is but you may want to look at this meter instead. The one you linked is just fine but this one also shows power output and not just reflected power like the one you linked. If you really want to get into it, you could also purchase a dummy load for accurately testing power. There are several out there for CB use. I think Workman also makes one along with a company called Opek that also makes CB-related gear. Since your average, off-the-shelf 100% legal radio puts out 4 watts on AM and 12 watts on SSB, you'd need one that can handle that amount of power. Ideally, you'd want one that will handle more than you can put into it, so something like a 25-50w+ load would work just fine. That being said, I've used one of these before with a CB radio and it worked well. I just wouldn't throw a bunch of power into it for a long time, which isn't something you'd likely be doing anyways unless you crank the power up in the radio (don't do that) or purchase an amplifier (ditto). You don't necessarily need a dummy load but it might be nice to have just for testing purposes in case you're not 100% sure that radio actually works.

Also, don't forget to purchase a short (3-6ft) jumper to hook the meter to the radio. There are several on Amazon and some folks may sell a package deal made up of a meter and a jumper. Here's an example, although the shipping for it as more than the item itself. Either way, you'll need to get one that has PL-259 connectors on each end.

Radio Coaxial Mount Antenna Spring
The mounting location is actually really nice, and it was very easy to set up. If you want a more detailed explanation, I'd be happy to give one.

The Uniden 520 is a great choice for a basic radio. I've been using one for years with excellent results. It's really hard to beat for the size/money.

Consider the K30 magnet mount antenna for an alternative in that size.
I've used both it and the Little Wil and found the K30 to perform noticeably better. It's also less expensive:

http://www.amazon.com/K40-K-30-Stainless-Magnet-Antenna/dp/B000H2W270/ref=sr_1_2?ie=UTF8&qid=1417900765&sr=8-2&keywords=K30

The other commenter that suggested getting an SWR meter is also correct. These antennas all require some degree of adjustment for optimal performance. Just a basic meter will work fine.

http://www.amazon.com/Astatic-PDC1-100-Watt-Meter/dp/B004ULN610/ref=sr_1_1?ie=UTF8&qid=1417900872&sr=8-1&keywords=SWR+meter

And the jumper:
http://www.amazon.com/Procomm-Coaxial-Cable-Jumper-Connectors/dp/B003DRJ738/ref=pd_bxgy_auto_text_y

The meter and jumper is something you'll very rarely need (just when moving the setup to a different vehicle, for the most part) so if you husband has a friend into CB or HAM operation, he may be able to borrow one for a few minutes rather than buying.

Finally, you'll need some way to power the radio. The easiest way is with a lighter plug:
http://www.amazon.com/Roadpro-Fused-Replacement-Cigarette-Lighter/dp/B0016LG0CY/ref=sr_1_1?ie=UTF8&qid=1417901045&sr=8-1&keywords=lighter+plug

Just cut the connectors off the ends of the wires and splice it with the ones on the radio.

Alternatively, you can connect to the fuse box with an Add-A-Circuit. These come in different sizes depending on the fuses in your car. You can get one of these for less than $10 at any auto parts store.