Look in the yellow pages for Machine Shops. Not all of the do driveshafts but some do. Yes take your measurements but IF YOU CAN take the vehicle to the shop on a trailer or wrecker and leave it there.
I was a ship mechanic in the Navy and it was easier if the machinists came down and took the measurements for us. They can read the rulers more accurate.
The trick is not just getting the correct length on a driveshaft but making sure it is TRUE as opposed to a crooked pool stick.
