Lee Kramka in SF - excellent work, but higher prices than others.
Eric Drake in Berkeley, overhauls horns, he is also outstanding with mouthpieces and engraving. Has a great inventory of mouthpieces. Medium range/ reasonable prices on repair. Very skilled guy.
Stanroys Music, out of the way in Santa Rosa. Gary did a very good inexpensive job on a King Zephyr recently. He know's what he's doing and prices are very reasonable - $500 for repad/corks/felts/swedging. Has a "pro" overhaul that's a little more.