What you'll want to do is go to the Formica website and start looking at what all they offer there. You can get free samples and trust me, you'll want 'em. What you see on the computer won't look the same in person. I ordered multiple times before deciding on the one we wanted. Whenever possible, order the larger size of the samples, if they offer you a choice.
ETI will only install the Formica brand, so don't bother looking elsewhere. And there isn't any reason why you can't order multiple samples of the same one to see how it looks like it would as your actual countertop in the trailer. (yeah, did that with one that it turns out ETI wasn't willing to install (not Formica) - bummer, as I really liked it.) You tell ETI what you want and they order it for you (you don't have to pay for it, like you will for the flooring and fabric).
For flooring, start hitting flooring stores - the ones with far more samples in the store than just Lowe's/Home Depot and the like. I managed to get a sample of the flooring we wanted by writing to the mfgr and their local rep sent me a sample, which was great to have. It was large enough to stand on with both feet, so it was nice to feel how cushy it is.
You can also contact Pioneer Building Supply in Chilliwack for the flooring. I forget which brands they carry, but they have a large selection, so you shouldn't have any problems with them ordering it for you. You pay them directly for the flooring and they'll hold it until ETI picks it up from them.
For fabric - have fun! There's multiple places on line where you can get upholstery fabric. Many of them offer free samples. We ended up going with the Sunbrella brand, which is what many others have done. We went into a local upholstery store and were able to sit on a couch and chair with that brand of fabric, so we were able to see how soft it was (or rather much softer than we thought it would be for an indoor/outdoor type fabric).
When you get free fabric samples, they're gonna be small, so once you narrow it down you can always order a yard to see if you really like it. I was able to get a yard off ebay of what I thought would be my final decision. After seeing it as a large sample, I knew that's what I wanted. But, until I saw that larger piece, it was hard to be sure.
I got my fabric from Patio Lane and they matched the price from their ebay listing, which was a bit lower than off their web site. I also got free shipping and they had a coupon going, so I got even more off. I had the luxury of having it shipped here as I'm close enough to drive to ETI and hand it off to them. Others will have items like this shipped directly to ETI.
Have fun making your decisions!