For a capacitor, I'd suggest finding an appliance parts store unless it's a long trip and an RV parts outlet's nearby. Prices are crazy-different according to where they're sold. One that actually sells to repair places. There are service hour ratings on capacitors. and the label has coding that'll tell that to somebody who knows the game. I'm buying them now at a parts store that charges about half what my previous source did, and for a much higher rated part.
But for now, get whatever you can lay your hands on unless you can do without for a few days. If you can wait a few days, Amazon can send one right to your campground. No truck or toad required...
Years ago (like 40!) a friend and I did a lot of tinkering, and he'd done a lot of work on refrigeration systems. Told me that the act of cutting the tubing to replace a component would release flakes of corrosion that would cause blockages. Yes, there are inline filter kits that should be installed with a new compressor. He still took that position. That said, I have no science on the issue. Fact or lore, thought I'd mention it.