It would take a profesional carpenter an afternoon to bang one of these out if you gave him the dimensaions and everything. Still, at $65 an hour or whatever they go for it would be quite expensive plus the cost of materials and shipping it would be completely insane - I'm guessing it costs more to ship than the cost of materials plus the carpenter.
As for the t-molding, I'm no carpenter but the first time I routed slots for t-molding it took me literally 15 minutes from start to finish. I set up the router, cut a test piece, centered the t-molding, tweaked the router, cut a second test piece, was happy the t-molding was centered and then cut the sides of my cabinet. Seriously it's 15 minutes from start to finish - so easy.
If you have the money to spend on a carpenter and shipping the materials around I think you'd be better off buying a router, a slot cutting bit, a flush cutting bit, a jigsaw and some clamps. That's all I used to build my current cabinet and I'm doing just fine. For the record, it took me about 2 full weekends worth of work to put my cabinet together (roughly 6-8 hours per day for 4 days).