If you need pop up trailer supplies, you can visit your local hardware store, camper dealerships and online.
If you need supplies that require some searching, you can easily do a search for the specific supplies you need and find a dealer or online outlet to buy the part from without to much trouble.
Some of the supplies you might need for a 2001 or 2002 pop-up camper are extra taillights, tail light bulbs and such.
If you need supplies, you can look at online sites and make purchase that may save you money even after adding in shipping and handling. Popups are not expensive to buy for; you just need to shop around. If you find yourself camping and need some right away, you might try the local hardware store. These stores do sometimes carry parts and supplies we need.
I found a little hardwood store in Ohio last year that had pop-up supplies and was amazed that such a little store carried so many things. I guess being close to; a campground pays off for these small stores so they carry things all of us popups need. This make life easier when traveling, but that is not always the case.
I remember being in Oklahoma, a few years back and need a tail light bulb, and could not find one anywhere. Now I carry spares, and if someone needs one, I give it to them and as soon as I can, I replenish my supplies.
Pop up trailer supplies are in high demand all year long and I think stores near campgrounds are catching on to the idea of having some supplies on hand for campers in case of an emergency. This makes things easier for all of us pop-up camper owners.