Bates and Bates has a 33" and will do custom sizes. It is 12 gauge, I believe.

Should also be able to get something from Julien Sinks.

Two companies I wasn't familiar with. GW comes through again! Thanks so much, I've passed this along. You guys rock!

Was going to suggest Julien--we have one of their 0-radius 30" sinks and love it! It comes with its own SS drain/strainer basket, BTW (or it did when we purchased ours in 2006-07).

Dino Rachiele will make you any stainless sink you want.

I loved dealing with him - great guy.

Good luck,
Doc

Here is a link that might be useful: Rachiele stainless sinks

A 33" sink is a standard size and will fit into a 36" base. A 36" sink is non standard and will need at least a 39" base, which is also non standard in many cabinet lines. Custom, while available, will about triple the costs over choosing standard sizes.

Well nh, it sounds like your brother can charge your SIL more for those non standard cabinets. hmmm that could be interesting :)
You are so lucky to have a cabinet maker in the family.