Looking for a little help finding parts for a 2010 Toyota Matrix (130K Miles)

I've had this car for 15 years and it's held up well. I put off some repairs until recently, and I am struggling to find the right parts.

1. The window seals are totally cooked. I think this is the right part, but this source only does bulk orders. I found this one for what seems like a very reasonable price, but it is for a Corolla. Would the corolla one be compatible? Otherwise, does anyone know where I could buy a single set and/or what a reasonable price might be?

2. Years ago I was hauling kayaks on a roof rack that ripped off on the highway (I had just stopped and checked things and nobody was injured thankfully). The factory-installed roof rails (that run front to back on the roof) look like something took a bite out of them and I think must have been weakened by years in the Florida sun. I've been trying to find replacement ones, but all I seem to find online are roof racks that you mount to those running rails. The closest I've found is this, but I only need the vertical pieces if that makes sense. If anyone can help me find the right part # and/or an idea of what a reasonable price would be that would be awesome.

3. The top 3rd or so of the dipstick tube broke off and is gone. I asked one shop what it would cost to replace and they quoted me at $60 for the part and $300 for labor since it is not easily accessible. I'm fairly handy, is replacing a dipstick tube something I could realistically do myself?