I would suggest that you contact the couple of dealers that specialize in lefty guitars – they have more than a few Santa Cruz in stock, and that would be your best first choice. I would not recommend that you consider a custom for your first Santa Cruz – at least, not unless you’ve had the opportunity to spend a considerable amount of time with a few different ones just to make sure that the size you’re considering is really ideal, and hopefully you’ll get a sense of how different woods can flavor the tone.
You don’t really say why the Taylor is your favorite – is it size, or playability, or tone, or ?? – What other guitars have you had, and what would you consider your second favorite, and even third? Each of those may have qualities that you should consider when thinking about a Santa Cruz.
As soon as I read deep rich sound of mahogany, I flashed on a nice OOO, or OM, but maybe even a D-12. Those would also have the better trade-in or resale value if you decide to go custom at some point. The other guitar that I immediately thought of is an OMG in mahogany that I played in SoCal – but not a lefty. Still would have loved to justify that one –
A Santa Cruz guitar can open you up to a new level of experience in playing – there’s a lot to consider, but very few ways you can go wrong – feel free to ask away! You’d be hard pressed to find a group of better enablers!