Seems to me that with new counter & vessel sink the only thing significantly raised is the bottom of the sink. You’ll also have to do some plumbing modifications to add under sink piping & of course now there’s a problem with either where backsplash was with the old counter or with the mirror which starts at backsplash height. Of course you’ll also need new faucets. It’ll be like pulling a thread. Do you like vessel sinks? They‘re decorative & generally a lot more costly than a bathroom sink which you can get for less than $100. If you already know it’s hard to find a 40” counter (I don’t know that), then how about get a new counter, you can get a quartz or granite remnant from a stone fabricator, get an undermount sink to maximize counter space, and have the vanity built up from the bottom. I know that can be done - a frame built to raise the vanity. Check out having vanity professionally refinished to clean up the oak - or professionally painted if you want to change color. Can’t say how much this will cost but how long will you be in this house & how much inconvenience is the too low vanity for the people using it every day? That will tell you if it’s worth it. It’s also a value add improvement to house.

Since the vanity is between two walls, I'd purchase a cabinet with appropriate filler to fill the entire space, then have a counter templated. I wouldn't want the vanity floating in the hole between walls. Build it in, like the current one is. You can still have open shelving or legs on the bottom if that's what you like.

Yes that’s the floor tile. It’s porcelain. https://www.tileshop.com/products/annie-selke-ikat-blue-ceramic-wall-and-floor-tile-20-x-20-in-680871. The mirror is all chrome, can’t really tell from pic and I feel the shape was reminiscent of the pattern.

I disagree. I actually have this set up. Our vanity is too small for 2 sinks without looking silly. Plenty of room to brush your teeth or wash your hands while your spouse is at the sink. Also because the faucets are positioned to the far ends of the sink, when you are standing in front of the faucet, there is plenty of room. Michael - it is very useful. I would know.